annotate Doc/lib/libstdtypes.tex @ 17581:c1937faabb23 2.1

Added support for optional explanation parameter to the \versionadded macro. Refactored do_cmd_versionadded() and do_cmd_versionchanged() to do most of the work in a helper function, with the do_cmd_*() wrappers just supplying a portion of the replacement text.
author Fred Drake <fdrake@acm.org>
date Wed, 18 Apr 2001 17:29:14 +0000
parents 68bd96e426e3
children 4d7fb24fe795 bf94af396b1e
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1 \section{Built-in Types \label{types}}
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2
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3 The following sections describe the standard types that are built into
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4 the interpreter. These are the numeric types, sequence types, and
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5 several others, including types themselves. There is no explicit
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6 Boolean type; use integers instead.
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7 \indexii{built-in}{types}
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8 \indexii{Boolean}{type}
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9
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10 Some operations are supported by several object types; in particular,
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11 all objects can be compared, tested for truth value, and converted to
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12 a string (with the \code{`\textrm{\ldots}`} notation). The latter
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13 conversion is implicitly used when an object is written by the
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14 \keyword{print}\stindex{print} statement.
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15
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16
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17 \subsection{Truth Value Testing \label{truth}}
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18
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19 Any object can be tested for truth value, for use in an \keyword{if} or
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20 \keyword{while} condition or as operand of the Boolean operations below.
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21 The following values are considered false:
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22 \stindex{if}
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23 \stindex{while}
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24 \indexii{truth}{value}
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25 \indexii{Boolean}{operations}
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26 \index{false}
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27
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28 \begin{itemize}
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29
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30 \item \code{None}
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31 \withsubitem{(Built-in object)}{\ttindex{None}}
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32
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33 \item zero of any numeric type, for example, \code{0}, \code{0L},
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34 \code{0.0}, \code{0j}.
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35
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36 \item any empty sequence, for example, \code{''}, \code{()}, \code{[]}.
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37
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38 \item any empty mapping, for example, \code{\{\}}.
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39
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40 \item instances of user-defined classes, if the class defines a
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41 \method{__nonzero__()} or \method{__len__()} method, when that
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42 method returns zero.\footnote{Additional information on these
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43 special methods may be found in the \citetitle[../ref/ref.html]{Python
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44 Reference Manual}.}
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45
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46 \end{itemize}
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47
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48 All other values are considered true --- so objects of many types are
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49 always true.
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50 \index{true}
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51
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52 Operations and built-in functions that have a Boolean result always
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53 return \code{0} for false and \code{1} for true, unless otherwise
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54 stated. (Important exception: the Boolean operations
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55 \samp{or}\opindex{or} and \samp{and}\opindex{and} always return one of
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56 their operands.)
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57
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58
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59 \subsection{Boolean Operations \label{boolean}}
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60
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61 These are the Boolean operations, ordered by ascending priority:
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62 \indexii{Boolean}{operations}
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63
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64 \begin{tableiii}{c|l|c}{code}{Operation}{Result}{Notes}
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65 \lineiii{\var{x} or \var{y}}
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66 {if \var{x} is false, then \var{y}, else \var{x}}{(1)}
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67 \lineiii{\var{x} and \var{y}}
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68 {if \var{x} is false, then \var{x}, else \var{y}}{(1)}
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69 \hline
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70 \lineiii{not \var{x}}
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71 {if \var{x} is false, then \code{1}, else \code{0}}{(2)}
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72 \end{tableiii}
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73 \opindex{and}
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74 \opindex{or}
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75 \opindex{not}
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76
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77 \noindent
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78 Notes:
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79
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80 \begin{description}
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81
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82 \item[(1)]
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83 These only evaluate their second argument if needed for their outcome.
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84
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85 \item[(2)]
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86 \samp{not} has a lower priority than non-Boolean operators, so
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87 \code{not \var{a} == \var{b}} is interpreted as \code{not (\var{a} ==
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88 \var{b})}, and \code{\var{a} == not \var{b}} is a syntax error.
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89
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90 \end{description}
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91
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92
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93 \subsection{Comparisons \label{comparisons}}
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94
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95 Comparison operations are supported by all objects. They all have the
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96 same priority (which is higher than that of the Boolean operations).
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97 Comparisons can be chained arbitrarily; for example, \code{\var{x} <
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98 \var{y} <= \var{z}} is equivalent to \code{\var{x} < \var{y} and
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99 \var{y} <= \var{z}}, except that \var{y} is evaluated only once (but
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100 in both cases \var{z} is not evaluated at all when \code{\var{x} <
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101 \var{y}} is found to be false).
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102 \indexii{chaining}{comparisons}
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103
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104 This table summarizes the comparison operations:
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105
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106 \begin{tableiii}{c|l|c}{code}{Operation}{Meaning}{Notes}
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107 \lineiii{<}{strictly less than}{}
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108 \lineiii{<=}{less than or equal}{}
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109 \lineiii{>}{strictly greater than}{}
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110 \lineiii{>=}{greater than or equal}{}
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111 \lineiii{==}{equal}{}
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112 \lineiii{!=}{not equal}{(1)}
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113 \lineiii{<>}{not equal}{(1)}
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114 \lineiii{is}{object identity}{}
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115 \lineiii{is not}{negated object identity}{}
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116 \end{tableiii}
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117 \indexii{operator}{comparison}
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118 \opindex{==} % XXX *All* others have funny characters < ! >
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119 \opindex{is}
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120 \opindex{is not}
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121
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122 \noindent
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123 Notes:
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124
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125 \begin{description}
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126
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127 \item[(1)]
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128 \code{<>} and \code{!=} are alternate spellings for the same operator.
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129 (I couldn't choose between \ABC{} and C! :-)
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130 \index{ABC language@\ABC{} language}
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131 \index{language!ABC@\ABC{}}
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132 \indexii{C}{language}
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133 \code{!=} is the preferred spelling; \code{<>} is obsolescent.
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134
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135 \end{description}
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136
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137 Objects of different types, except different numeric types, never
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138 compare equal; such objects are ordered consistently but arbitrarily
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139 (so that sorting a heterogeneous array yields a consistent result).
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140 Furthermore, some types (for example, file objects) support only a
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141 degenerate notion of comparison where any two objects of that type are
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142 unequal. Again, such objects are ordered arbitrarily but
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143 consistently.
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144 \indexii{object}{numeric}
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145 \indexii{objects}{comparing}
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146
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147 Instances of a class normally compare as non-equal unless the class
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148 \withsubitem{(instance method)}{\ttindex{__cmp__()}}
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149 defines the \method{__cmp__()} method. Refer to the
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150 \citetitle[../ref/customization.html]{Python Reference Manual} for
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151 information on the use of this method to effect object comparisons.
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152
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153 \strong{Implementation note:} Objects of different types except
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154 numbers are ordered by their type names; objects of the same types
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155 that don't support proper comparison are ordered by their address.
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156
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157 Two more operations with the same syntactic priority,
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158 \samp{in}\opindex{in} and \samp{not in}\opindex{not in}, are supported
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159 only by sequence types (below).
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160
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161
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162 \subsection{Numeric Types \label{typesnumeric}}
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163
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164 There are four numeric types: \dfn{plain integers}, \dfn{long integers},
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165 \dfn{floating point numbers}, and \dfn{complex numbers}.
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166 Plain integers (also just called \dfn{integers})
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167 are implemented using \ctype{long} in C, which gives them at least 32
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168 bits of precision. Long integers have unlimited precision. Floating
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169 point numbers are implemented using \ctype{double} in C. All bets on
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170 their precision are off unless you happen to know the machine you are
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171 working with.
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172 \obindex{numeric}
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173 \obindex{integer}
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174 \obindex{long integer}
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175 \obindex{floating point}
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176 \obindex{complex number}
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177 \indexii{C}{language}
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178
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179 Complex numbers have a real and imaginary part, which are both
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180 implemented using \ctype{double} in C. To extract these parts from
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181 a complex number \var{z}, use \code{\var{z}.real} and \code{\var{z}.imag}.
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182
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183 Numbers are created by numeric literals or as the result of built-in
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184 functions and operators. Unadorned integer literals (including hex
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185 and octal numbers) yield plain integers. Integer literals with an
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186 \character{L} or \character{l} suffix yield long integers
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187 (\character{L} is preferred because \samp{1l} looks too much like
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188 eleven!). Numeric literals containing a decimal point or an exponent
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189 sign yield floating point numbers. Appending \character{j} or
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190 \character{J} to a numeric literal yields a complex number.
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191 \indexii{numeric}{literals}
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192 \indexii{integer}{literals}
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193 \indexiii{long}{integer}{literals}
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194 \indexii{floating point}{literals}
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195 \indexii{complex number}{literals}
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196 \indexii{hexadecimal}{literals}
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197 \indexii{octal}{literals}
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198
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199 Python fully supports mixed arithmetic: when a binary arithmetic
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200 operator has operands of different numeric types, the operand with the
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201 ``smaller'' type is converted to that of the other, where plain
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202 integer is smaller than long integer is smaller than floating point is
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203 smaller than complex.
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204 Comparisons between numbers of mixed type use the same rule.\footnote{
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205 As a consequence, the list \code{[1, 2]} is considered equal
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206 to \code{[1.0, 2.0]}, and similar for tuples.
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207 } The functions \function{int()}, \function{long()}, \function{float()},
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208 and \function{complex()} can be used
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209 to coerce numbers to a specific type.
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210 \index{arithmetic}
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211 \bifuncindex{int}
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212 \bifuncindex{long}
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213 \bifuncindex{float}
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214 \bifuncindex{complex}
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215
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216 All numeric types support the following operations, sorted by
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217 ascending priority (operations in the same box have the same
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218 priority; all numeric operations have a higher priority than
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219 comparison operations):
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220
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221 \begin{tableiii}{c|l|c}{code}{Operation}{Result}{Notes}
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222 \lineiii{\var{x} + \var{y}}{sum of \var{x} and \var{y}}{}
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223 \lineiii{\var{x} - \var{y}}{difference of \var{x} and \var{y}}{}
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224 \hline
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225 \lineiii{\var{x} * \var{y}}{product of \var{x} and \var{y}}{}
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226 \lineiii{\var{x} / \var{y}}{quotient of \var{x} and \var{y}}{(1)}
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227 \lineiii{\var{x} \%{} \var{y}}{remainder of \code{\var{x} / \var{y}}}{}
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228 \hline
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229 \lineiii{-\var{x}}{\var{x} negated}{}
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230 \lineiii{+\var{x}}{\var{x} unchanged}{}
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231 \hline
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232 \lineiii{abs(\var{x})}{absolute value or magnitude of \var{x}}{}
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233 \lineiii{int(\var{x})}{\var{x} converted to integer}{(2)}
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234 \lineiii{long(\var{x})}{\var{x} converted to long integer}{(2)}
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235 \lineiii{float(\var{x})}{\var{x} converted to floating point}{}
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236 \lineiii{complex(\var{re},\var{im})}{a complex number with real part \var{re}, imaginary part \var{im}. \var{im} defaults to zero.}{}
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237 \lineiii{\var{c}.conjugate()}{conjugate of the complex number \var{c}}{}
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238 \lineiii{divmod(\var{x}, \var{y})}{the pair \code{(\var{x} / \var{y}, \var{x} \%{} \var{y})}}{(3)}
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239 \lineiii{pow(\var{x}, \var{y})}{\var{x} to the power \var{y}}{}
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240 \lineiii{\var{x} ** \var{y}}{\var{x} to the power \var{y}}{}
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241 \end{tableiii}
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242 \indexiii{operations on}{numeric}{types}
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243 \withsubitem{(complex number method)}{\ttindex{conjugate()}}
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244
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245 \noindent
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246 Notes:
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247 \begin{description}
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248
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249 \item[(1)]
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250 For (plain or long) integer division, the result is an integer.
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251 The result is always rounded towards minus infinity: 1/2 is 0,
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252 (-1)/2 is -1, 1/(-2) is -1, and (-1)/(-2) is 0. Note that the result
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253 is a long integer if either operand is a long integer, regardless of
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254 the numeric value.
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255 \indexii{integer}{division}
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256 \indexiii{long}{integer}{division}
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257
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258 \item[(2)]
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259 Conversion from floating point to (long or plain) integer may round or
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260 truncate as in C; see functions \function{floor()} and
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261 \function{ceil()} in the \refmodule{math}\refbimodindex{math} module
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262 for well-defined conversions.
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263 \withsubitem{(in module math)}{\ttindex{floor()}\ttindex{ceil()}}
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264 \indexii{numeric}{conversions}
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265 \indexii{C}{language}
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266
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267 \item[(3)]
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268 See section \ref{built-in-funcs}, ``Built-in Functions,'' for a full
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269 description.
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270
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271 \end{description}
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272 % XXXJH exceptions: overflow (when? what operations?) zerodivision
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273
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274 \subsubsection{Bit-string Operations on Integer Types \label{bitstring-ops}}
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275 \nodename{Bit-string Operations}
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276
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277 Plain and long integer types support additional operations that make
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278 sense only for bit-strings. Negative numbers are treated as their 2's
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279 complement value (for long integers, this assumes a sufficiently large
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280 number of bits that no overflow occurs during the operation).
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281
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282 The priorities of the binary bit-wise operations are all lower than
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283 the numeric operations and higher than the comparisons; the unary
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284 operation \samp{\~} has the same priority as the other unary numeric
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285 operations (\samp{+} and \samp{-}).
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286
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287 This table lists the bit-string operations sorted in ascending
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288 priority (operations in the same box have the same priority):
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289
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290 \begin{tableiii}{c|l|c}{code}{Operation}{Result}{Notes}
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291 \lineiii{\var{x} | \var{y}}{bitwise \dfn{or} of \var{x} and \var{y}}{}
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292 \lineiii{\var{x} \^{} \var{y}}{bitwise \dfn{exclusive or} of \var{x} and \var{y}}{}
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293 \lineiii{\var{x} \&{} \var{y}}{bitwise \dfn{and} of \var{x} and \var{y}}{}
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294 \lineiii{\var{x} << \var{n}}{\var{x} shifted left by \var{n} bits}{(1), (2)}
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295 \lineiii{\var{x} >> \var{n}}{\var{x} shifted right by \var{n} bits}{(1), (3)}
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296 \hline
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297 \lineiii{\~\var{x}}{the bits of \var{x} inverted}{}
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298 \end{tableiii}
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299 \indexiii{operations on}{integer}{types}
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300 \indexii{bit-string}{operations}
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301 \indexii{shifting}{operations}
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302 \indexii{masking}{operations}
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303
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304 \noindent
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305 Notes:
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306 \begin{description}
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307 \item[(1)] Negative shift counts are illegal and cause a
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308 \exception{ValueError} to be raised.
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309 \item[(2)] A left shift by \var{n} bits is equivalent to
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310 multiplication by \code{pow(2, \var{n})} without overflow check.
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311 \item[(3)] A right shift by \var{n} bits is equivalent to
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312 division by \code{pow(2, \var{n})} without overflow check.
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313 \end{description}
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314
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315
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316 \subsection{Sequence Types \label{typesseq}}
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317
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318 There are six sequence types: strings, Unicode strings, lists,
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319 tuples, buffers, and xrange objects.
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320
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321 Strings literals are written in single or double quotes:
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322 \code{'xyzzy'}, \code{"frobozz"}. See chapter 2 of the
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323 \citetitle[../ref/strings.html]{Python Reference Manual} for more about
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324 string literals. Unicode strings are much like strings, but are
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325 specified in the syntax using a preceeding \character{u} character:
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326 \code{u'abc'}, \code{u"def"}. Lists are constructed with square brackets,
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327 separating items with commas: \code{[a, b, c]}. Tuples are
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328 constructed by the comma operator (not within square brackets), with
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329 or without enclosing parentheses, but an empty tuple must have the
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330 enclosing parentheses, e.g., \code{a, b, c} or \code{()}. A single
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331 item tuple must have a trailing comma, e.g., \code{(d,)}. Buffers are
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332 not directly supported by Python syntax, but can be created by calling the
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333 builtin function \function{buffer()}.\bifuncindex{buffer} XRanges
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334 objects are similar to buffers in that there is no specific syntax to
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335 create them, but they are created using the \function{xrange()}
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336 function.\bifuncindex{xrange}
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337 \obindex{sequence}
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338 \obindex{string}
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339 \obindex{Unicode}
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340 \obindex{buffer}
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341 \obindex{tuple}
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342 \obindex{list}
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343 \obindex{xrange}
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344
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345 Sequence types support the following operations. The \samp{in} and
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346 \samp{not in} operations have the same priorities as the comparison
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347 operations. The \samp{+} and \samp{*} operations have the same
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348 priority as the corresponding numeric operations.\footnote{They must
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349 have since the parser can't tell the type of the operands.}
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350
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351 This table lists the sequence operations sorted in ascending priority
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352 (operations in the same box have the same priority). In the table,
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353 \var{s} and \var{t} are sequences of the same type; \var{n}, \var{i}
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354 and \var{j} are integers:
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355
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356 \begin{tableiii}{c|l|c}{code}{Operation}{Result}{Notes}
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357 \lineiii{\var{x} in \var{s}}{\code{1} if an item of \var{s} is equal to \var{x}, else \code{0}}{}
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358 \lineiii{\var{x} not in \var{s}}{\code{0} if an item of \var{s} is
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359 equal to \var{x}, else \code{1}}{}
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360 \hline
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361 \lineiii{\var{s} + \var{t}}{the concatenation of \var{s} and \var{t}}{}
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362 \lineiii{\var{s} * \var{n}\textrm{,} \var{n} * \var{s}}{\var{n} copies of \var{s} concatenated}{(1)}
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363 \hline
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364 \lineiii{\var{s}[\var{i}]}{\var{i}'th item of \var{s}, origin 0}{(2)}
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365 \lineiii{\var{s}[\var{i}:\var{j}]}{slice of \var{s} from \var{i} to \var{j}}{(2), (3)}
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366 \hline
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367 \lineiii{len(\var{s})}{length of \var{s}}{}
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368 \lineiii{min(\var{s})}{smallest item of \var{s}}{}
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369 \lineiii{max(\var{s})}{largest item of \var{s}}{}
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370 \end{tableiii}
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371 \indexiii{operations on}{sequence}{types}
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372 \bifuncindex{len}
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373 \bifuncindex{min}
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374 \bifuncindex{max}
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375 \indexii{concatenation}{operation}
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376 \indexii{repetition}{operation}
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377 \indexii{subscript}{operation}
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378 \indexii{slice}{operation}
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379 \opindex{in}
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380 \opindex{not in}
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381
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382 \noindent
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383 Notes:
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384
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385 \begin{description}
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386 \item[(1)] Values of \var{n} less than \code{0} are treated as
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387 \code{0} (which yields an empty sequence of the same type as
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388 \var{s}).
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389
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390 \item[(2)] If \var{i} or \var{j} is negative, the index is relative to
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391 the end of the string, i.e., \code{len(\var{s}) + \var{i}} or
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392 \code{len(\var{s}) + \var{j}} is substituted. But note that \code{-0} is
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393 still \code{0}.
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394
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395 \item[(3)] The slice of \var{s} from \var{i} to \var{j} is defined as
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396 the sequence of items with index \var{k} such that \code{\var{i} <=
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397 \var{k} < \var{j}}. If \var{i} or \var{j} is greater than
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398 \code{len(\var{s})}, use \code{len(\var{s})}. If \var{i} is omitted,
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399 use \code{0}. If \var{j} is omitted, use \code{len(\var{s})}. If
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400 \var{i} is greater than or equal to \var{j}, the slice is empty.
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401 \end{description}
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402
10156
0f7d694bc334 Make sure all HTML pages generated from this section have reasonable
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403
13933
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404 \subsubsection{String Methods \label{string-methods}}
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405
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406 These are the string methods which both 8-bit strings and Unicode
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407 objects support:
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408
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409 \begin{methoddesc}[string]{capitalize}{}
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410 Return a copy of the string with only its first character capitalized.
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411 \end{methoddesc}
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412
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413 \begin{methoddesc}[string]{center}{width}
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414 Return centered in a string of length \var{width}. Padding is done
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415 using spaces.
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416 \end{methoddesc}
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417
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418 \begin{methoddesc}[string]{count}{sub\optional{, start\optional{, end}}}
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419 Return the number of occurrences of substring \var{sub} in string
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420 S\code{[\var{start}:\var{end}]}. Optional arguments \var{start} and
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421 \var{end} are interpreted as in slice notation.
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422 \end{methoddesc}
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423
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424 \begin{methoddesc}[string]{encode}{\optional{encoding\optional{,errors}}}
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425 Return an encoded version of the string. Default encoding is the current
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426 default string encoding. \var{errors} may be given to set a different
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diff changeset
427 error handling scheme. The default for \var{errors} is
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428 \code{'strict'}, meaning that encoding errors raise a
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429 \exception{ValueError}. Other possible values are \code{'ignore'} and
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430 \code{'replace'}.
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12aec3381c94 Marc-Andre Lemburg <mal@lemburg.com> noted that the encode() string method
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431 \versionadded{2.0}
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432 \end{methoddesc}
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433
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434 \begin{methoddesc}[string]{endswith}{suffix\optional{, start\optional{, end}}}
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435 Return true if the string ends with the specified \var{suffix},
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436 otherwise return false. With optional \var{start}, test beginning at
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437 that position. With optional \var{end}, stop comparing at that position.
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438 \end{methoddesc}
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439
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440 \begin{methoddesc}[string]{expandtabs}{\optional{tabsize}}
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441 Return a copy of the string where all tab characters are expanded
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442 using spaces. If \var{tabsize} is not given, a tab size of \code{8}
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443 characters is assumed.
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444 \end{methoddesc}
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445
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446 \begin{methoddesc}[string]{find}{sub\optional{, start\optional{, end}}}
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447 Return the lowest index in the string where substring \var{sub} is
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448 found, such that \var{sub} is contained in the range [\var{start},
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449 \var{end}). Optional arguments \var{start} and \var{end} are
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450 interpreted as in slice notation. Return \code{-1} if \var{sub} is
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451 not found.
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452 \end{methoddesc}
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diff changeset
453
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454 \begin{methoddesc}[string]{index}{sub\optional{, start\optional{, end}}}
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455 Like \method{find()}, but raise \exception{ValueError} when the
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456 substring is not found.
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457 \end{methoddesc}
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diff changeset
458
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diff changeset
459 \begin{methoddesc}[string]{isalnum}{}
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diff changeset
460 Return true if all characters in the string are alphanumeric and there
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461 is at least one character, false otherwise.
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462 \end{methoddesc}
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diff changeset
463
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464 \begin{methoddesc}[string]{isalpha}{}
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diff changeset
465 Return true if all characters in the string are alphabetic and there
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466 is at least one character, false otherwise.
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diff changeset
467 \end{methoddesc}
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diff changeset
468
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diff changeset
469 \begin{methoddesc}[string]{isdigit}{}
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diff changeset
470 Return true if there are only digit characters, false otherwise.
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diff changeset
471 \end{methoddesc}
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diff changeset
472
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473 \begin{methoddesc}[string]{islower}{}
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474 Return true if all cased characters in the string are lowercase and
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
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475 there is at least one cased character, false otherwise.
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diff changeset
476 \end{methoddesc}
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
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diff changeset
477
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diff changeset
478 \begin{methoddesc}[string]{isspace}{}
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diff changeset
479 Return true if there are only whitespace characters in the string and
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
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diff changeset
480 the string is not empty, false otherwise.
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
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diff changeset
481 \end{methoddesc}
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diff changeset
482
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
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diff changeset
483 \begin{methoddesc}[string]{istitle}{}
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
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diff changeset
484 Return true if the string is a titlecased string, i.e.\ uppercase
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
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diff changeset
485 characters may only follow uncased characters and lowercase characters
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diff changeset
486 only cased ones. Return false otherwise.
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diff changeset
487 \end{methoddesc}
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diff changeset
488
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
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diff changeset
489 \begin{methoddesc}[string]{isupper}{}
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
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diff changeset
490 Return true if all cased characters in the string are uppercase and
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
Fred Drake <fdrake@acm.org>
parents: 13894
diff changeset
491 there is at least one cased character, false otherwise.
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parents: 13894
diff changeset
492 \end{methoddesc}
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diff changeset
493
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
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diff changeset
494 \begin{methoddesc}[string]{join}{seq}
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parents: 13894
diff changeset
495 Return a string which is the concatenation of the strings in the
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
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diff changeset
496 sequence \var{seq}. The separator between elements is the string
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
Fred Drake <fdrake@acm.org>
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diff changeset
497 providing this method.
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
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diff changeset
498 \end{methoddesc}
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
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diff changeset
499
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
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diff changeset
500 \begin{methoddesc}[string]{ljust}{width}
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
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parents: 13894
diff changeset
501 Return the string left justified in a string of length \var{width}.
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
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parents: 13894
diff changeset
502 Padding is done using spaces. The original string is returned if
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
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parents: 13894
diff changeset
503 \var{width} is less than \code{len(\var{s})}.
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
Fred Drake <fdrake@acm.org>
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diff changeset
504 \end{methoddesc}
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Fred Drake <fdrake@acm.org>
parents: 13894
diff changeset
505
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
Fred Drake <fdrake@acm.org>
parents: 13894
diff changeset
506 \begin{methoddesc}[string]{lower}{}
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
Fred Drake <fdrake@acm.org>
parents: 13894
diff changeset
507 Return a copy of the string converted to lowercase.
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
Fred Drake <fdrake@acm.org>
parents: 13894
diff changeset
508 \end{methoddesc}
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
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parents: 13894
diff changeset
509
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
Fred Drake <fdrake@acm.org>
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diff changeset
510 \begin{methoddesc}[string]{lstrip}{}
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
Fred Drake <fdrake@acm.org>
parents: 13894
diff changeset
511 Return a copy of the string with leading whitespace removed.
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
Fred Drake <fdrake@acm.org>
parents: 13894
diff changeset
512 \end{methoddesc}
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
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parents: 13894
diff changeset
513
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
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parents: 13894
diff changeset
514 \begin{methoddesc}[string]{replace}{old, new\optional{, maxsplit}}
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
Fred Drake <fdrake@acm.org>
parents: 13894
diff changeset
515 Return a copy of the string with all occurrences of substring
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
Fred Drake <fdrake@acm.org>
parents: 13894
diff changeset
516 \var{old} replaced by \var{new}. If the optional argument
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
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parents: 13894
diff changeset
517 \var{maxsplit} is given, only the first \var{maxsplit} occurrences are
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
Fred Drake <fdrake@acm.org>
parents: 13894
diff changeset
518 replaced.
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
Fred Drake <fdrake@acm.org>
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diff changeset
519 \end{methoddesc}
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
Fred Drake <fdrake@acm.org>
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diff changeset
520
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
Fred Drake <fdrake@acm.org>
parents: 13894
diff changeset
521 \begin{methoddesc}[string]{rfind}{sub \optional{,start \optional{,end}}}
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
Fred Drake <fdrake@acm.org>
parents: 13894
diff changeset
522 Return the highest index in the string where substring \var{sub} is
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
Fred Drake <fdrake@acm.org>
parents: 13894
diff changeset
523 found, such that \var{sub} is contained within s[start,end]. Optional
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
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parents: 13894
diff changeset
524 arguments \var{start} and \var{end} are interpreted as in slice
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
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parents: 13894
diff changeset
525 notation. Return \code{-1} on failure.
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
Fred Drake <fdrake@acm.org>
parents: 13894
diff changeset
526 \end{methoddesc}
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
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diff changeset
527
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
Fred Drake <fdrake@acm.org>
parents: 13894
diff changeset
528 \begin{methoddesc}[string]{rindex}{sub\optional{, start\optional{, end}}}
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
Fred Drake <fdrake@acm.org>
parents: 13894
diff changeset
529 Like \method{rfind()} but raises \exception{ValueError} when the
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
Fred Drake <fdrake@acm.org>
parents: 13894
diff changeset
530 substring \var{sub} is not found.
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
Fred Drake <fdrake@acm.org>
parents: 13894
diff changeset
531 \end{methoddesc}
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Fred Drake <fdrake@acm.org>
parents: 13894
diff changeset
532
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
Fred Drake <fdrake@acm.org>
parents: 13894
diff changeset
533 \begin{methoddesc}[string]{rjust}{width}
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
Fred Drake <fdrake@acm.org>
parents: 13894
diff changeset
534 Return the string right justified in a string of length \var{width}.
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
Fred Drake <fdrake@acm.org>
parents: 13894
diff changeset
535 Padding is done using spaces. The original string is returned if
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
Fred Drake <fdrake@acm.org>
parents: 13894
diff changeset
536 \var{width} is less than \code{len(\var{s})}.
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
Fred Drake <fdrake@acm.org>
parents: 13894
diff changeset
537 \end{methoddesc}
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
Fred Drake <fdrake@acm.org>
parents: 13894
diff changeset
538
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
Fred Drake <fdrake@acm.org>
parents: 13894
diff changeset
539 \begin{methoddesc}[string]{rstrip}{}
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
Fred Drake <fdrake@acm.org>
parents: 13894
diff changeset
540 Return a copy of the string with trailing whitespace removed.
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
Fred Drake <fdrake@acm.org>
parents: 13894
diff changeset
541 \end{methoddesc}
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
Fred Drake <fdrake@acm.org>
parents: 13894
diff changeset
542
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
Fred Drake <fdrake@acm.org>
parents: 13894
diff changeset
543 \begin{methoddesc}[string]{split}{\optional{sep \optional{,maxsplit}}}
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
Fred Drake <fdrake@acm.org>
parents: 13894
diff changeset
544 Return a list of the words in the string, using \var{sep} as the
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
Fred Drake <fdrake@acm.org>
parents: 13894
diff changeset
545 delimiter string. If \var{maxsplit} is given, at most \var{maxsplit}
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
Fred Drake <fdrake@acm.org>
parents: 13894
diff changeset
546 splits are done. If \var{sep} is not specified or \code{None}, any
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
Fred Drake <fdrake@acm.org>
parents: 13894
diff changeset
547 whitespace string is a separator.
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
Fred Drake <fdrake@acm.org>
parents: 13894
diff changeset
548 \end{methoddesc}
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
Fred Drake <fdrake@acm.org>
parents: 13894
diff changeset
549
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
Fred Drake <fdrake@acm.org>
parents: 13894
diff changeset
550 \begin{methoddesc}[string]{splitlines}{\optional{keepends}}
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
Fred Drake <fdrake@acm.org>
parents: 13894
diff changeset
551 Return a list of the lines in the string, breaking at line
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
Fred Drake <fdrake@acm.org>
parents: 13894
diff changeset
552 boundaries. Line breaks are not included in the resulting list unless
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
Fred Drake <fdrake@acm.org>
parents: 13894
diff changeset
553 \var{keepends} is given and true.
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
Fred Drake <fdrake@acm.org>
parents: 13894
diff changeset
554 \end{methoddesc}
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
Fred Drake <fdrake@acm.org>
parents: 13894
diff changeset
555
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
Fred Drake <fdrake@acm.org>
parents: 13894
diff changeset
556 \begin{methoddesc}[string]{startswith}{prefix\optional{, start\optional{, end}}}
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
Fred Drake <fdrake@acm.org>
parents: 13894
diff changeset
557 Return true if string starts with the \var{prefix}, otherwise
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
Fred Drake <fdrake@acm.org>
parents: 13894
diff changeset
558 return false. With optional \var{start}, test string beginning at
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
Fred Drake <fdrake@acm.org>
parents: 13894
diff changeset
559 that position. With optional \var{end}, stop comparing string at that
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
Fred Drake <fdrake@acm.org>
parents: 13894
diff changeset
560 position.
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
Fred Drake <fdrake@acm.org>
parents: 13894
diff changeset
561 \end{methoddesc}
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
Fred Drake <fdrake@acm.org>
parents: 13894
diff changeset
562
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
Fred Drake <fdrake@acm.org>
parents: 13894
diff changeset
563 \begin{methoddesc}[string]{strip}{}
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
Fred Drake <fdrake@acm.org>
parents: 13894
diff changeset
564 Return a copy of the string with leading and trailing whitespace
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
Fred Drake <fdrake@acm.org>
parents: 13894
diff changeset
565 removed.
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
Fred Drake <fdrake@acm.org>
parents: 13894
diff changeset
566 \end{methoddesc}
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
Fred Drake <fdrake@acm.org>
parents: 13894
diff changeset
567
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
Fred Drake <fdrake@acm.org>
parents: 13894
diff changeset
568 \begin{methoddesc}[string]{swapcase}{}
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
Fred Drake <fdrake@acm.org>
parents: 13894
diff changeset
569 Return a copy of the string with uppercase characters converted to
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
Fred Drake <fdrake@acm.org>
parents: 13894
diff changeset
570 lowercase and vice versa.
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
Fred Drake <fdrake@acm.org>
parents: 13894
diff changeset
571 \end{methoddesc}
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
Fred Drake <fdrake@acm.org>
parents: 13894
diff changeset
572
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
Fred Drake <fdrake@acm.org>
parents: 13894
diff changeset
573 \begin{methoddesc}[string]{title}{}
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
Fred Drake <fdrake@acm.org>
parents: 13894
diff changeset
574 Return a titlecased version of, i.e.\ words start with uppercase
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
Fred Drake <fdrake@acm.org>
parents: 13894
diff changeset
575 characters, all remaining cased characters are lowercase.
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
Fred Drake <fdrake@acm.org>
parents: 13894
diff changeset
576 \end{methoddesc}
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
Fred Drake <fdrake@acm.org>
parents: 13894
diff changeset
577
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
Fred Drake <fdrake@acm.org>
parents: 13894
diff changeset
578 \begin{methoddesc}[string]{translate}{table\optional{, deletechars}}
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
Fred Drake <fdrake@acm.org>
parents: 13894
diff changeset
579 Return a copy of the string where all characters occurring in the
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
Fred Drake <fdrake@acm.org>
parents: 13894
diff changeset
580 optional argument \var{deletechars} are removed, and the remaining
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
Fred Drake <fdrake@acm.org>
parents: 13894
diff changeset
581 characters have been mapped through the given translation table, which
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
Fred Drake <fdrake@acm.org>
parents: 13894
diff changeset
582 must be a string of length 256.
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
Fred Drake <fdrake@acm.org>
parents: 13894
diff changeset
583 \end{methoddesc}
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
Fred Drake <fdrake@acm.org>
parents: 13894
diff changeset
584
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
Fred Drake <fdrake@acm.org>
parents: 13894
diff changeset
585 \begin{methoddesc}[string]{upper}{}
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
Fred Drake <fdrake@acm.org>
parents: 13894
diff changeset
586 Return a copy of the string converted to uppercase.
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
Fred Drake <fdrake@acm.org>
parents: 13894
diff changeset
587 \end{methoddesc}
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
Fred Drake <fdrake@acm.org>
parents: 13894
diff changeset
588
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
Fred Drake <fdrake@acm.org>
parents: 13894
diff changeset
589
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
Fred Drake <fdrake@acm.org>
parents: 13894
diff changeset
590 \subsubsection{String Formatting Operations \label{typesseq-strings}}
8730
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
591
14552
a8d1c030b19f Add some index entries to make it easier to find information on
Fred Drake <fdrake@acm.org>
parents: 14520
diff changeset
592 \index{formatting, string}
a8d1c030b19f Add some index entries to make it easier to find information on
Fred Drake <fdrake@acm.org>
parents: 14520
diff changeset
593 \index{string!formatting}
a8d1c030b19f Add some index entries to make it easier to find information on
Fred Drake <fdrake@acm.org>
parents: 14520
diff changeset
594 \index{printf-style formatting}
a8d1c030b19f Add some index entries to make it easier to find information on
Fred Drake <fdrake@acm.org>
parents: 14520
diff changeset
595 \index{sprintf-style formatting}
a8d1c030b19f Add some index entries to make it easier to find information on
Fred Drake <fdrake@acm.org>
parents: 14520
diff changeset
596
16285
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
597 String and Unicode objects have one unique built-in operation: the
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
598 \code{\%} operator (modulo). Given \code{\var{format} \%
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
599 \var{values}} (where \var{format} is a string or Unicode object),
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
600 \code{\%} conversion specifications in \var{format} are replaced with
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
601 zero or more elements of \var{values}. The effect is similar to the
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
602 using \cfunction{sprintf()} in the C language. If \var{format} is a
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
603 Unicode object, or if any of the objects being converted using the
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
604 \code{\%s} conversion are Unicode objects, the result will be a
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
605 Unicode object as well.
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
606
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
607 If \var{format} requires a single argument, \var{values} may be a
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
608 single non-tuple object. \footnote{A tuple object in this case should
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
609 be a singleton.} Otherwise, \var{values} must be a tuple with
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
610 exactly the number of items specified by the format string, or a
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
611 single mapping object (for example, a dictionary).
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
612
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
613 A conversion specifier contains two or more characters and has the
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
614 following components, which must occur in this order:
8730
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
615
16285
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
616 \begin{enumerate}
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
617 \item The \character{\%} character, which marks the start of the
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
618 specifier.
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
619 \item Mapping key value (optional), consisting of an identifier in
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
620 parentheses (for example, \code{(somename)}).
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
621 \item Conversion flags (optional), which affect the result of some
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
622 conversion types.
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
623 \item Minimum field width (optional). If specified as an
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
624 \character{*} (asterisk), the actual width is read from the
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
625 next element of the tuple in \var{values}, and the object to
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
626 convert comes after the minimum field width and optional
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
627 precision.
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
628 \item Precision (optional), given as a \character{.} (dot) followed
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
629 by the precision. If specified as \character{*} (an
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
630 asterisk), the actual width is read from the next element of
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
631 the tuple in \var{values}, and the value to convert comes after
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
632 the precision.
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
633 \item Length modifier (optional).
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
634 \item Conversion type.
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
635 \end{enumerate}
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Fred Drake <fdrake@acm.org>
parents:
diff changeset
636
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
637 If the right argument is a dictionary (or any kind of mapping), then
16285
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
638 the formats in the string \emph{must} have a parenthesized key into
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
639 that dictionary inserted immediately after the \character{\%}
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
640 character, and each format formats the corresponding entry from the
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
641 mapping. For example:
8730
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
642
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
643 \begin{verbatim}
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
644 >>> count = 2
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
645 >>> language = 'Python'
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
646 >>> print '%(language)s has %(count)03d quote types.' % vars()
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
647 Python has 002 quote types.
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
648 \end{verbatim}
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
649
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
650 In this case no \code{*} specifiers may occur in a format (since they
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
651 require a sequential parameter list).
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
652
16285
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
653 The conversion flag characters are:
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
654
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
655 \begin{tableii}{c|l}{character}{Flag}{Meaning}
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
656 \lineii{\#}{The value conversion will use the ``alternate form''
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
657 (where defined below).}
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
658 \lineii{0}{The conversion will be zero padded.}
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
659 \lineii{-}{The converted value is left adjusted (overrides
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
660 \character{-}).}
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
661 \lineii{{~}}{(a space) A blank should be left before a positive number
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
662 (or empty string) produced by a signed conversion.}
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
663 \lineii{+}{A sign character (\character{+} or \character{-}) will
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
664 precede the conversion (overrides a "space" flag).}
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
665 \end{tableii}
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
666
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
667 The length modifier may be \code{h}, \code{l}, and \code{L} may be
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
668 present, but are ignored as they are not necessary for Python.
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
669
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
670 The conversion types are:
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
671
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
672 \begin{tableii}{c|l}{character}{Conversion}{Meaning}
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
673 \lineii{d}{Signed integer decimal.}
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
674 \lineii{i}{Signed integer decimal.}
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
675 \lineii{o}{Unsigned octal.}
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
676 \lineii{u}{Unsigned decimal.}
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
677 \lineii{x}{Unsigned hexidecimal (lowercase).}
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
678 \lineii{X}{Unsigned hexidecimal (uppercase).}
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
679 \lineii{e}{Floating point exponential format (lowercase).}
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
680 \lineii{E}{Floating point exponential format (uppercase).}
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
681 \lineii{f}{Floating point decimal format.}
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
682 \lineii{F}{Floating point decimal format.}
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
683 \lineii{g}{Same as \character{e} if exponent is greater than -4 or
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
684 less than precision, \character{f} otherwise.}
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
685 \lineii{G}{Same as \character{E} if exponent is greater than -4 or
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
686 less than precision, \character{F} otherwise.}
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
687 \lineii{c}{Single character (accepts integer or single character
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
688 string).}
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
689 \lineii{r}{String (converts any python object using
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
690 \function{repr()}).}
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
691 \lineii{s}{String (converts any python object using
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
692 \function{str()}).}
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
693 \lineii{\%}{No argument is converted, results in a \character{\%}
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
694 character in the result. (The complete specification is
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
695 \code{\%\%}.)}
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
696 \end{tableii}
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
697
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
698 % XXX Examples?
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
699
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
700
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
701 Since Python strings have an explicit length, \code{\%s} conversions
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
702 do not assume that \code{'\e0'} is the end of the string.
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
703
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
704 For safety reasons, floating point precisions are clipped to 50;
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
705 \code{\%f} conversions for numbers whose absolute value is over 1e25
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
706 are replaced by \code{\%g} conversions.\footnote{
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
707 These numbers are fairly arbitrary. They are intended to
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
708 avoid printing endless strings of meaningless digits without hampering
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
709 correct use and without having to know the exact precision of floating
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
710 point values on a particular machine.
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
711 } All other errors raise exceptions.
15e0c10092bb Massively improved documentation for string formatting operations,
Fred Drake <fdrake@acm.org>
parents: 15926
diff changeset
712
8730
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
713 Additional string operations are defined in standard module
13967
7b7ee58901fb Document the range type, as suggested by Denis S. Otkidach
Fred Drake <fdrake@acm.org>
parents: 13933
diff changeset
714 \refmodule{string} and in built-in module \refmodule{re}.
8730
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
715 \refstmodindex{string}
8882
b28b84e6a429 re is standard, not built-in.
Fred Drake <fdrake@acm.org>
parents: 8734
diff changeset
716 \refstmodindex{re}
8730
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
717
13967
7b7ee58901fb Document the range type, as suggested by Denis S. Otkidach
Fred Drake <fdrake@acm.org>
parents: 13933
diff changeset
718
14044
a905c5aa0691 As pointed out by Denis S. Otkidach <den@analyt.chem.msu.ru>, xrange()
Fred Drake <fdrake@acm.org>
parents: 13967
diff changeset
719 \subsubsection{XRange Type \label{typesseq-xrange}}
13967
7b7ee58901fb Document the range type, as suggested by Denis S. Otkidach
Fred Drake <fdrake@acm.org>
parents: 13933
diff changeset
720
15005
0cf5111bf09c Use \obindex{...} instead of \indexii{...}{type} in many places; this is
Fred Drake <fdrake@acm.org>
parents: 14710
diff changeset
721 The xrange\obindex{xrange} type is an immutable sequence which is
14044
a905c5aa0691 As pointed out by Denis S. Otkidach <den@analyt.chem.msu.ru>, xrange()
Fred Drake <fdrake@acm.org>
parents: 13967
diff changeset
722 commonly used for looping. The advantage of the xrange type is that an
a905c5aa0691 As pointed out by Denis S. Otkidach <den@analyt.chem.msu.ru>, xrange()
Fred Drake <fdrake@acm.org>
parents: 13967
diff changeset
723 xrange object will always take the same amount of memory, no matter the
13967
7b7ee58901fb Document the range type, as suggested by Denis S. Otkidach
Fred Drake <fdrake@acm.org>
parents: 13933
diff changeset
724 size of the range it represents. There are no consistent performance
7b7ee58901fb Document the range type, as suggested by Denis S. Otkidach
Fred Drake <fdrake@acm.org>
parents: 13933
diff changeset
725 advantages.
7b7ee58901fb Document the range type, as suggested by Denis S. Otkidach
Fred Drake <fdrake@acm.org>
parents: 13933
diff changeset
726
14044
a905c5aa0691 As pointed out by Denis S. Otkidach <den@analyt.chem.msu.ru>, xrange()
Fred Drake <fdrake@acm.org>
parents: 13967
diff changeset
727 XRange objects behave like tuples, and offer a single method:
13967
7b7ee58901fb Document the range type, as suggested by Denis S. Otkidach
Fred Drake <fdrake@acm.org>
parents: 13933
diff changeset
728
14044
a905c5aa0691 As pointed out by Denis S. Otkidach <den@analyt.chem.msu.ru>, xrange()
Fred Drake <fdrake@acm.org>
parents: 13967
diff changeset
729 \begin{methoddesc}[xrange]{tolist}{}
a905c5aa0691 As pointed out by Denis S. Otkidach <den@analyt.chem.msu.ru>, xrange()
Fred Drake <fdrake@acm.org>
parents: 13967
diff changeset
730 Return a list object which represents the same values as the xrange
13967
7b7ee58901fb Document the range type, as suggested by Denis S. Otkidach
Fred Drake <fdrake@acm.org>
parents: 13933
diff changeset
731 object.
7b7ee58901fb Document the range type, as suggested by Denis S. Otkidach
Fred Drake <fdrake@acm.org>
parents: 13933
diff changeset
732 \end{methoddesc}
7b7ee58901fb Document the range type, as suggested by Denis S. Otkidach
Fred Drake <fdrake@acm.org>
parents: 13933
diff changeset
733
7b7ee58901fb Document the range type, as suggested by Denis S. Otkidach
Fred Drake <fdrake@acm.org>
parents: 13933
diff changeset
734
10156
0f7d694bc334 Make sure all HTML pages generated from this section have reasonable
Fred Drake <fdrake@acm.org>
parents: 10147
diff changeset
735 \subsubsection{Mutable Sequence Types \label{typesseq-mutable}}
8730
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
736
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
737 List objects support additional operations that allow in-place
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
738 modification of the object.
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
739 These operations would be supported by other mutable sequence types
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
740 (when added to the language) as well.
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
741 Strings and tuples are immutable sequence types and such objects cannot
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
742 be modified once created.
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
743 The following operations are defined on mutable sequence types (where
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
744 \var{x} is an arbitrary object):
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
745 \indexiii{mutable}{sequence}{types}
15005
0cf5111bf09c Use \obindex{...} instead of \indexii{...}{type} in many places; this is
Fred Drake <fdrake@acm.org>
parents: 14710
diff changeset
746 \obindex{list}
8730
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
747
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
748 \begin{tableiii}{c|l|c}{code}{Operation}{Result}{Notes}
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
749 \lineiii{\var{s}[\var{i}] = \var{x}}
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
750 {item \var{i} of \var{s} is replaced by \var{x}}{}
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
751 \lineiii{\var{s}[\var{i}:\var{j}] = \var{t}}
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
752 {slice of \var{s} from \var{i} to \var{j} is replaced by \var{t}}{}
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
753 \lineiii{del \var{s}[\var{i}:\var{j}]}
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
754 {same as \code{\var{s}[\var{i}:\var{j}] = []}}{}
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
755 \lineiii{\var{s}.append(\var{x})}
12223
e82e82b3b9ad Merged changes from the 1.5.2p2 release.
Fred Drake <fdrake@acm.org>
parents: 11463
diff changeset
756 {same as \code{\var{s}[len(\var{s}):len(\var{s})] = [\var{x}]}}{(1)}
9318
8a26e55e18b8 Document the new list.extend() method. Interesting enough, the
Barry Warsaw <barry@python.org>
parents: 9083
diff changeset
757 \lineiii{\var{s}.extend(\var{x})}
12223
e82e82b3b9ad Merged changes from the 1.5.2p2 release.
Fred Drake <fdrake@acm.org>
parents: 11463
diff changeset
758 {same as \code{\var{s}[len(\var{s}):len(\var{s})] = \var{x}}}{(2)}
8730
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
759 \lineiii{\var{s}.count(\var{x})}
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
760 {return number of \var{i}'s for which \code{\var{s}[\var{i}] == \var{x}}}{}
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
761 \lineiii{\var{s}.index(\var{x})}
12223
e82e82b3b9ad Merged changes from the 1.5.2p2 release.
Fred Drake <fdrake@acm.org>
parents: 11463
diff changeset
762 {return smallest \var{i} such that \code{\var{s}[\var{i}] == \var{x}}}{(3)}
8730
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
763 \lineiii{\var{s}.insert(\var{i}, \var{x})}
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
764 {same as \code{\var{s}[\var{i}:\var{i}] = [\var{x}]}
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
765 if \code{\var{i} >= 0}}{}
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
766 \lineiii{\var{s}.pop(\optional{\var{i}})}
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
767 {same as \code{\var{x} = \var{s}[\var{i}]; del \var{s}[\var{i}]; return \var{x}}}{(4)}
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
768 \lineiii{\var{s}.remove(\var{x})}
12223
e82e82b3b9ad Merged changes from the 1.5.2p2 release.
Fred Drake <fdrake@acm.org>
parents: 11463
diff changeset
769 {same as \code{del \var{s}[\var{s}.index(\var{x})]}}{(3)}
8730
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
770 \lineiii{\var{s}.reverse()}
12223
e82e82b3b9ad Merged changes from the 1.5.2p2 release.
Fred Drake <fdrake@acm.org>
parents: 11463
diff changeset
771 {reverses the items of \var{s} in place}{(5)}
8730
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
772 \lineiii{\var{s}.sort(\optional{\var{cmpfunc}})}
12223
e82e82b3b9ad Merged changes from the 1.5.2p2 release.
Fred Drake <fdrake@acm.org>
parents: 11463
diff changeset
773 {sort the items of \var{s} in place}{(5), (6)}
8730
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
774 \end{tableiii}
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
775 \indexiv{operations on}{mutable}{sequence}{types}
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
776 \indexiii{operations on}{sequence}{types}
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
777 \indexiii{operations on}{list}{type}
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
778 \indexii{subscript}{assignment}
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
779 \indexii{slice}{assignment}
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
780 \stindex{del}
10156
0f7d694bc334 Make sure all HTML pages generated from this section have reasonable
Fred Drake <fdrake@acm.org>
parents: 10147
diff changeset
781 \withsubitem{(list method)}{
11183
1e0b1967be7f In note mentioning [].remove()'s exception, tell what exception is
Fred Drake <fdrake@acm.org>
parents: 11100
diff changeset
782 \ttindex{append()}\ttindex{extend()}\ttindex{count()}\ttindex{index()}
1e0b1967be7f In note mentioning [].remove()'s exception, tell what exception is
Fred Drake <fdrake@acm.org>
parents: 11100
diff changeset
783 \ttindex{insert()}\ttindex{pop()}\ttindex{remove()}\ttindex{reverse()}
9523
ed6cacddc6c6 Fix indexing of func_code attribute; this is on a function, not a code
Fred Drake <fdrake@acm.org>
parents: 9461
diff changeset
784 \ttindex{sort()}}
8730
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
785 \noindent
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
786 Notes:
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
787 \begin{description}
12223
e82e82b3b9ad Merged changes from the 1.5.2p2 release.
Fred Drake <fdrake@acm.org>
parents: 11463
diff changeset
788 \item[(1)] The C implementation of Python has historically accepted
e82e82b3b9ad Merged changes from the 1.5.2p2 release.
Fred Drake <fdrake@acm.org>
parents: 11463
diff changeset
789 multiple parameters and implicitly joined them into a tuple; this
13222
5dd381aeb23b Update version numbering from 1.6 to 2.0.
Fred Drake <fdrake@acm.org>
parents: 12223
diff changeset
790 no longer works in Python 2.0. Use of this misfeature has been
12223
e82e82b3b9ad Merged changes from the 1.5.2p2 release.
Fred Drake <fdrake@acm.org>
parents: 11463
diff changeset
791 deprecated since Python 1.4.
e82e82b3b9ad Merged changes from the 1.5.2p2 release.
Fred Drake <fdrake@acm.org>
parents: 11463
diff changeset
792
e82e82b3b9ad Merged changes from the 1.5.2p2 release.
Fred Drake <fdrake@acm.org>
parents: 11463
diff changeset
793 \item[(2)] Raises an exception when \var{x} is not a list object. The
e82e82b3b9ad Merged changes from the 1.5.2p2 release.
Fred Drake <fdrake@acm.org>
parents: 11463
diff changeset
794 \method{extend()} method is experimental and not supported by
e82e82b3b9ad Merged changes from the 1.5.2p2 release.
Fred Drake <fdrake@acm.org>
parents: 11463
diff changeset
795 mutable sequence types other than lists.
e82e82b3b9ad Merged changes from the 1.5.2p2 release.
Fred Drake <fdrake@acm.org>
parents: 11463
diff changeset
796
e82e82b3b9ad Merged changes from the 1.5.2p2 release.
Fred Drake <fdrake@acm.org>
parents: 11463
diff changeset
797 \item[(3)] Raises \exception{ValueError} when \var{x} is not found in
11183
1e0b1967be7f In note mentioning [].remove()'s exception, tell what exception is
Fred Drake <fdrake@acm.org>
parents: 11100
diff changeset
798 \var{s}.
1e0b1967be7f In note mentioning [].remove()'s exception, tell what exception is
Fred Drake <fdrake@acm.org>
parents: 11100
diff changeset
799
13780
e20fe0052680 fixing a minor spelling mistake
Peter Schneider-Kamp <nowonder@nowonder.de>
parents: 13777
diff changeset
800 \item[(4)] The \method{pop()} method is only supported by the list and
13777
b3903e05017f Stop lying about [].pop() being experimental! There is no backing it out
Fred Drake <fdrake@acm.org>
parents: 13772
diff changeset
801 array types. The optional argument \var{i} defaults to \code{-1},
b3903e05017f Stop lying about [].pop() being experimental! There is no backing it out
Fred Drake <fdrake@acm.org>
parents: 13772
diff changeset
802 so that by default the last item is removed and returned.
12223
e82e82b3b9ad Merged changes from the 1.5.2p2 release.
Fred Drake <fdrake@acm.org>
parents: 11463
diff changeset
803
e82e82b3b9ad Merged changes from the 1.5.2p2 release.
Fred Drake <fdrake@acm.org>
parents: 11463
diff changeset
804 \item[(5)] The \method{sort()} and \method{reverse()} methods modify the
e82e82b3b9ad Merged changes from the 1.5.2p2 release.
Fred Drake <fdrake@acm.org>
parents: 11463
diff changeset
805 list in place for economy of space when sorting or reversing a large
e82e82b3b9ad Merged changes from the 1.5.2p2 release.
Fred Drake <fdrake@acm.org>
parents: 11463
diff changeset
806 list. They don't return the sorted or reversed list to remind you
e82e82b3b9ad Merged changes from the 1.5.2p2 release.
Fred Drake <fdrake@acm.org>
parents: 11463
diff changeset
807 of this side effect.
e82e82b3b9ad Merged changes from the 1.5.2p2 release.
Fred Drake <fdrake@acm.org>
parents: 11463
diff changeset
808
e82e82b3b9ad Merged changes from the 1.5.2p2 release.
Fred Drake <fdrake@acm.org>
parents: 11463
diff changeset
809 \item[(6)] The \method{sort()} method takes an optional argument
8730
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
810 specifying a comparison function of two arguments (list items) which
11183
1e0b1967be7f In note mentioning [].remove()'s exception, tell what exception is
Fred Drake <fdrake@acm.org>
parents: 11100
diff changeset
811 should return \code{-1}, \code{0} or \code{1} depending on whether
1e0b1967be7f In note mentioning [].remove()'s exception, tell what exception is
Fred Drake <fdrake@acm.org>
parents: 11100
diff changeset
812 the first argument is considered smaller than, equal to, or larger
1e0b1967be7f In note mentioning [].remove()'s exception, tell what exception is
Fred Drake <fdrake@acm.org>
parents: 11100
diff changeset
813 than the second argument. Note that this slows the sorting process
1e0b1967be7f In note mentioning [].remove()'s exception, tell what exception is
Fred Drake <fdrake@acm.org>
parents: 11100
diff changeset
814 down considerably; e.g. to sort a list in reverse order it is much
1e0b1967be7f In note mentioning [].remove()'s exception, tell what exception is
Fred Drake <fdrake@acm.org>
parents: 11100
diff changeset
815 faster to use calls to the methods \method{sort()} and
1e0b1967be7f In note mentioning [].remove()'s exception, tell what exception is
Fred Drake <fdrake@acm.org>
parents: 11100
diff changeset
816 \method{reverse()} than to use the built-in function
1e0b1967be7f In note mentioning [].remove()'s exception, tell what exception is
Fred Drake <fdrake@acm.org>
parents: 11100
diff changeset
817 \function{sort()} with a comparison function that reverses the
1e0b1967be7f In note mentioning [].remove()'s exception, tell what exception is
Fred Drake <fdrake@acm.org>
parents: 11100
diff changeset
818 ordering of the elements.
8730
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
819 \end{description}
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
820
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
821
9083
bc41e86c938c Markup nits.
Fred Drake <fdrake@acm.org>
parents: 9034
diff changeset
822 \subsection{Mapping Types \label{typesmapping}}
15005
0cf5111bf09c Use \obindex{...} instead of \indexii{...}{type} in many places; this is
Fred Drake <fdrake@acm.org>
parents: 14710
diff changeset
823 \obindex{mapping}
0cf5111bf09c Use \obindex{...} instead of \indexii{...}{type} in many places; this is
Fred Drake <fdrake@acm.org>
parents: 14710
diff changeset
824 \obindex{dictionary}
8730
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
825
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
826 A \dfn{mapping} object maps values of one type (the key type) to
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
827 arbitrary objects. Mappings are mutable objects. There is currently
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
828 only one standard mapping type, the \dfn{dictionary}. A dictionary's keys are
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
829 almost arbitrary values. The only types of values not acceptable as
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
830 keys are values containing lists or dictionaries or other mutable
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
831 types that are compared by value rather than by object identity.
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
832 Numeric types used for keys obey the normal rules for numeric
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
833 comparison: if two numbers compare equal (e.g. \code{1} and
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
834 \code{1.0}) then they can be used interchangeably to index the same
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
835 dictionary entry.
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
836
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
837 Dictionaries are created by placing a comma-separated list of
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
838 \code{\var{key}: \var{value}} pairs within braces, for example:
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
839 \code{\{'jack': 4098, 'sjoerd': 4127\}} or
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
840 \code{\{4098: 'jack', 4127: 'sjoerd'\}}.
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
841
10968
5ba2e4ce58cb Some clarifications on operations for mapping types, based on comments
Fred Drake <fdrake@acm.org>
parents: 10785
diff changeset
842 The following operations are defined on mappings (where \var{a} and
5ba2e4ce58cb Some clarifications on operations for mapping types, based on comments
Fred Drake <fdrake@acm.org>
parents: 10785
diff changeset
843 \var{b} are mappings, \var{k} is a key, and \var{v} and \var{x} are
5ba2e4ce58cb Some clarifications on operations for mapping types, based on comments
Fred Drake <fdrake@acm.org>
parents: 10785
diff changeset
844 arbitrary objects):
8730
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
845 \indexiii{operations on}{mapping}{types}
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
846 \indexiii{operations on}{dictionary}{type}
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
847 \stindex{del}
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
848 \bifuncindex{len}
10156
0f7d694bc334 Make sure all HTML pages generated from this section have reasonable
Fred Drake <fdrake@acm.org>
parents: 10147
diff changeset
849 \withsubitem{(dictionary method)}{
0f7d694bc334 Make sure all HTML pages generated from this section have reasonable
Fred Drake <fdrake@acm.org>
parents: 10147
diff changeset
850 \ttindex{clear()}
0f7d694bc334 Make sure all HTML pages generated from this section have reasonable
Fred Drake <fdrake@acm.org>
parents: 10147
diff changeset
851 \ttindex{copy()}
0f7d694bc334 Make sure all HTML pages generated from this section have reasonable
Fred Drake <fdrake@acm.org>
parents: 10147
diff changeset
852 \ttindex{has_key()}
0f7d694bc334 Make sure all HTML pages generated from this section have reasonable
Fred Drake <fdrake@acm.org>
parents: 10147
diff changeset
853 \ttindex{items()}
0f7d694bc334 Make sure all HTML pages generated from this section have reasonable
Fred Drake <fdrake@acm.org>
parents: 10147
diff changeset
854 \ttindex{keys()}
0f7d694bc334 Make sure all HTML pages generated from this section have reasonable
Fred Drake <fdrake@acm.org>
parents: 10147
diff changeset
855 \ttindex{update()}
0f7d694bc334 Make sure all HTML pages generated from this section have reasonable
Fred Drake <fdrake@acm.org>
parents: 10147
diff changeset
856 \ttindex{values()}
9523
ed6cacddc6c6 Fix indexing of func_code attribute; this is on a function, not a code
Fred Drake <fdrake@acm.org>
parents: 9461
diff changeset
857 \ttindex{get()}}
10968
5ba2e4ce58cb Some clarifications on operations for mapping types, based on comments
Fred Drake <fdrake@acm.org>
parents: 10785
diff changeset
858
5ba2e4ce58cb Some clarifications on operations for mapping types, based on comments
Fred Drake <fdrake@acm.org>
parents: 10785
diff changeset
859 \begin{tableiii}{c|l|c}{code}{Operation}{Result}{Notes}
5ba2e4ce58cb Some clarifications on operations for mapping types, based on comments
Fred Drake <fdrake@acm.org>
parents: 10785
diff changeset
860 \lineiii{len(\var{a})}{the number of items in \var{a}}{}
5ba2e4ce58cb Some clarifications on operations for mapping types, based on comments
Fred Drake <fdrake@acm.org>
parents: 10785
diff changeset
861 \lineiii{\var{a}[\var{k}]}{the item of \var{a} with key \var{k}}{(1)}
13764
fdbc8730d356 Two minor nits from Gerry Weiner (no working email address) about
Fred Drake <fdrake@acm.org>
parents: 13222
diff changeset
862 \lineiii{\var{a}[\var{k}] = \var{v}}
fdbc8730d356 Two minor nits from Gerry Weiner (no working email address) about
Fred Drake <fdrake@acm.org>
parents: 13222
diff changeset
863 {set \code{\var{a}[\var{k}]} to \var{v}}
10968
5ba2e4ce58cb Some clarifications on operations for mapping types, based on comments
Fred Drake <fdrake@acm.org>
parents: 10785
diff changeset
864 {}
5ba2e4ce58cb Some clarifications on operations for mapping types, based on comments
Fred Drake <fdrake@acm.org>
parents: 10785
diff changeset
865 \lineiii{del \var{a}[\var{k}]}
5ba2e4ce58cb Some clarifications on operations for mapping types, based on comments
Fred Drake <fdrake@acm.org>
parents: 10785
diff changeset
866 {remove \code{\var{a}[\var{k}]} from \var{a}}
5ba2e4ce58cb Some clarifications on operations for mapping types, based on comments
Fred Drake <fdrake@acm.org>
parents: 10785
diff changeset
867 {(1)}
5ba2e4ce58cb Some clarifications on operations for mapping types, based on comments
Fred Drake <fdrake@acm.org>
parents: 10785
diff changeset
868 \lineiii{\var{a}.clear()}{remove all items from \code{a}}{}
5ba2e4ce58cb Some clarifications on operations for mapping types, based on comments
Fred Drake <fdrake@acm.org>
parents: 10785
diff changeset
869 \lineiii{\var{a}.copy()}{a (shallow) copy of \code{a}}{}
5ba2e4ce58cb Some clarifications on operations for mapping types, based on comments
Fred Drake <fdrake@acm.org>
parents: 10785
diff changeset
870 \lineiii{\var{a}.has_key(\var{k})}
5ba2e4ce58cb Some clarifications on operations for mapping types, based on comments
Fred Drake <fdrake@acm.org>
parents: 10785
diff changeset
871 {\code{1} if \var{a} has a key \var{k}, else \code{0}}
5ba2e4ce58cb Some clarifications on operations for mapping types, based on comments
Fred Drake <fdrake@acm.org>
parents: 10785
diff changeset
872 {}
5ba2e4ce58cb Some clarifications on operations for mapping types, based on comments
Fred Drake <fdrake@acm.org>
parents: 10785
diff changeset
873 \lineiii{\var{a}.items()}
5ba2e4ce58cb Some clarifications on operations for mapping types, based on comments
Fred Drake <fdrake@acm.org>
parents: 10785
diff changeset
874 {a copy of \var{a}'s list of (\var{key}, \var{value}) pairs}
5ba2e4ce58cb Some clarifications on operations for mapping types, based on comments
Fred Drake <fdrake@acm.org>
parents: 10785
diff changeset
875 {(2)}
5ba2e4ce58cb Some clarifications on operations for mapping types, based on comments
Fred Drake <fdrake@acm.org>
parents: 10785
diff changeset
876 \lineiii{\var{a}.keys()}{a copy of \var{a}'s list of keys}{(2)}
5ba2e4ce58cb Some clarifications on operations for mapping types, based on comments
Fred Drake <fdrake@acm.org>
parents: 10785
diff changeset
877 \lineiii{\var{a}.update(\var{b})}
13764
fdbc8730d356 Two minor nits from Gerry Weiner (no working email address) about
Fred Drake <fdrake@acm.org>
parents: 13222
diff changeset
878 {\code{for k in \var{b}.keys(): \var{a}[k] = \var{b}[k]}}
10968
5ba2e4ce58cb Some clarifications on operations for mapping types, based on comments
Fred Drake <fdrake@acm.org>
parents: 10785
diff changeset
879 {(3)}
5ba2e4ce58cb Some clarifications on operations for mapping types, based on comments
Fred Drake <fdrake@acm.org>
parents: 10785
diff changeset
880 \lineiii{\var{a}.values()}{a copy of \var{a}'s list of values}{(2)}
5ba2e4ce58cb Some clarifications on operations for mapping types, based on comments
Fred Drake <fdrake@acm.org>
parents: 10785
diff changeset
881 \lineiii{\var{a}.get(\var{k}\optional{, \var{x}})}
5ba2e4ce58cb Some clarifications on operations for mapping types, based on comments
Fred Drake <fdrake@acm.org>
parents: 10785
diff changeset
882 {\code{\var{a}[\var{k}]} if \code{\var{a}.has_key(\var{k})},
5ba2e4ce58cb Some clarifications on operations for mapping types, based on comments
Fred Drake <fdrake@acm.org>
parents: 10785
diff changeset
883 else \var{x}}
5ba2e4ce58cb Some clarifications on operations for mapping types, based on comments
Fred Drake <fdrake@acm.org>
parents: 10785
diff changeset
884 {(4)}
13894
77b9e041b595 Barry's patch to document the new setdefault() method. Slightly
Guido van Rossum <guido@python.org>
parents: 13780
diff changeset
885 \lineiii{\var{a}.setdefault(\var{k}\optional{, \var{x}})}
77b9e041b595 Barry's patch to document the new setdefault() method. Slightly
Guido van Rossum <guido@python.org>
parents: 13780
diff changeset
886 {\code{\var{a}[\var{k}]} if \code{\var{a}.has_key(\var{k})},
77b9e041b595 Barry's patch to document the new setdefault() method. Slightly
Guido van Rossum <guido@python.org>
parents: 13780
diff changeset
887 else \var{x} (also setting it)}
77b9e041b595 Barry's patch to document the new setdefault() method. Slightly
Guido van Rossum <guido@python.org>
parents: 13780
diff changeset
888 {(5)}
15522
aaa54752e4ba "Documentation" for {}.popitem().
Guido van Rossum <guido@python.org>
parents: 15463
diff changeset
889 \lineiii{\var{a}.popitem()}
aaa54752e4ba "Documentation" for {}.popitem().
Guido van Rossum <guido@python.org>
parents: 15463
diff changeset
890 {remove and return an arbitrary (\var{key}, \var{value}) pair}
aaa54752e4ba "Documentation" for {}.popitem().
Guido van Rossum <guido@python.org>
parents: 15463
diff changeset
891 {(6)}
10968
5ba2e4ce58cb Some clarifications on operations for mapping types, based on comments
Fred Drake <fdrake@acm.org>
parents: 10785
diff changeset
892 \end{tableiii}
5ba2e4ce58cb Some clarifications on operations for mapping types, based on comments
Fred Drake <fdrake@acm.org>
parents: 10785
diff changeset
893
8730
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
894 \noindent
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
895 Notes:
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
896 \begin{description}
10968
5ba2e4ce58cb Some clarifications on operations for mapping types, based on comments
Fred Drake <fdrake@acm.org>
parents: 10785
diff changeset
897 \item[(1)] Raises a \exception{KeyError} exception if \var{k} is not
5ba2e4ce58cb Some clarifications on operations for mapping types, based on comments
Fred Drake <fdrake@acm.org>
parents: 10785
diff changeset
898 in the map.
8730
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
899
12223
e82e82b3b9ad Merged changes from the 1.5.2p2 release.
Fred Drake <fdrake@acm.org>
parents: 11463
diff changeset
900 \item[(2)] Keys and values are listed in random order. If
e82e82b3b9ad Merged changes from the 1.5.2p2 release.
Fred Drake <fdrake@acm.org>
parents: 11463
diff changeset
901 \method{keys()} and \method{values()} are called with no intervening
e82e82b3b9ad Merged changes from the 1.5.2p2 release.
Fred Drake <fdrake@acm.org>
parents: 11463
diff changeset
902 modifications to the dictionary, the two lists will directly
e82e82b3b9ad Merged changes from the 1.5.2p2 release.
Fred Drake <fdrake@acm.org>
parents: 11463
diff changeset
903 correspond. This allows the creation of \code{(\var{value},
e82e82b3b9ad Merged changes from the 1.5.2p2 release.
Fred Drake <fdrake@acm.org>
parents: 11463
diff changeset
904 \var{key})} pairs using \function{map()}: \samp{pairs = map(None,
e82e82b3b9ad Merged changes from the 1.5.2p2 release.
Fred Drake <fdrake@acm.org>
parents: 11463
diff changeset
905 \var{a}.values(), \var{a}.keys())}.
8730
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
906
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
907 \item[(3)] \var{b} must be of the same type as \var{a}.
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
908
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
909 \item[(4)] Never raises an exception if \var{k} is not in the map,
12223
e82e82b3b9ad Merged changes from the 1.5.2p2 release.
Fred Drake <fdrake@acm.org>
parents: 11463
diff changeset
910 instead it returns \var{x}. \var{x} is optional; when \var{x} is not
10968
5ba2e4ce58cb Some clarifications on operations for mapping types, based on comments
Fred Drake <fdrake@acm.org>
parents: 10785
diff changeset
911 provided and \var{k} is not in the map, \code{None} is returned.
13894
77b9e041b595 Barry's patch to document the new setdefault() method. Slightly
Guido van Rossum <guido@python.org>
parents: 13780
diff changeset
912
77b9e041b595 Barry's patch to document the new setdefault() method. Slightly
Guido van Rossum <guido@python.org>
parents: 13780
diff changeset
913 \item[(5)] \function{setdefault()} is like \function{get()}, except
77b9e041b595 Barry's patch to document the new setdefault() method. Slightly
Guido van Rossum <guido@python.org>
parents: 13780
diff changeset
914 that if \var{k} is missing, \var{x} is both returned and inserted into
77b9e041b595 Barry's patch to document the new setdefault() method. Slightly
Guido van Rossum <guido@python.org>
parents: 13780
diff changeset
915 the dictionary as the value of \var{k}.
15522
aaa54752e4ba "Documentation" for {}.popitem().
Guido van Rossum <guido@python.org>
parents: 15463
diff changeset
916
aaa54752e4ba "Documentation" for {}.popitem().
Guido van Rossum <guido@python.org>
parents: 15463
diff changeset
917 \item[(6)] \function{popitem()} is useful to destructively iterate
aaa54752e4ba "Documentation" for {}.popitem().
Guido van Rossum <guido@python.org>
parents: 15463
diff changeset
918 over a dictionary, as often used in set algorithms.
8730
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
919 \end{description}
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
920
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
921
9083
bc41e86c938c Markup nits.
Fred Drake <fdrake@acm.org>
parents: 9034
diff changeset
922 \subsection{Other Built-in Types \label{typesother}}
8730
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
923
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
924 The interpreter supports several other kinds of objects.
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
925 Most of these support only one or two operations.
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
926
10241
f138ba72bf2d Update description of what modules "look like" when printed.
Fred Drake <fdrake@acm.org>
parents: 10156
diff changeset
927
10156
0f7d694bc334 Make sure all HTML pages generated from this section have reasonable
Fred Drake <fdrake@acm.org>
parents: 10147
diff changeset
928 \subsubsection{Modules \label{typesmodules}}
8730
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
929
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
930 The only special operation on a module is attribute access:
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
931 \code{\var{m}.\var{name}}, where \var{m} is a module and \var{name}
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
932 accesses a name defined in \var{m}'s symbol table. Module attributes
9558
fa867d8ee7eb Remove some remaining {\rm ...} constructs.
Fred Drake <fdrake@acm.org>
parents: 9523
diff changeset
933 can be assigned to. (Note that the \keyword{import} statement is not,
9034
182c9cbdf053 spoking --> speaking
Fred Drake <fdrake@acm.org>
parents: 8882
diff changeset
934 strictly speaking, an operation on a module object; \code{import
8730
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
935 \var{foo}} does not require a module object named \var{foo} to exist,
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
936 rather it requires an (external) \emph{definition} for a module named
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
937 \var{foo} somewhere.)
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
938
9558
fa867d8ee7eb Remove some remaining {\rm ...} constructs.
Fred Drake <fdrake@acm.org>
parents: 9523
diff changeset
939 A special member of every module is \member{__dict__}.
8730
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
940 This is the dictionary containing the module's symbol table.
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
941 Modifying this dictionary will actually change the module's symbol
9558
fa867d8ee7eb Remove some remaining {\rm ...} constructs.
Fred Drake <fdrake@acm.org>
parents: 9523
diff changeset
942 table, but direct assignment to the \member{__dict__} attribute is not
8730
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
943 possible (i.e., you can write \code{\var{m}.__dict__['a'] = 1}, which
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
944 defines \code{\var{m}.a} to be \code{1}, but you can't write
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
945 \code{\var{m}.__dict__ = \{\}}.
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
946
10241
f138ba72bf2d Update description of what modules "look like" when printed.
Fred Drake <fdrake@acm.org>
parents: 10156
diff changeset
947 Modules built into the interpreter are written like this:
f138ba72bf2d Update description of what modules "look like" when printed.
Fred Drake <fdrake@acm.org>
parents: 10156
diff changeset
948 \code{<module 'sys' (built-in)>}. If loaded from a file, they are
14557
a71385f8b4da Use \shortversion in a number of places.
Fred Drake <fdrake@acm.org>
parents: 14552
diff changeset
949 written as \code{<module 'os' from
a71385f8b4da Use \shortversion in a number of places.
Fred Drake <fdrake@acm.org>
parents: 14552
diff changeset
950 '/usr/local/lib/python\shortversion/os.pyc'>}.
10241
f138ba72bf2d Update description of what modules "look like" when printed.
Fred Drake <fdrake@acm.org>
parents: 10156
diff changeset
951
8730
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
952
10156
0f7d694bc334 Make sure all HTML pages generated from this section have reasonable
Fred Drake <fdrake@acm.org>
parents: 10147
diff changeset
953 \subsubsection{Classes and Class Instances \label{typesobjects}}
8730
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
954 \nodename{Classes and Instances}
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
955
12223
e82e82b3b9ad Merged changes from the 1.5.2p2 release.
Fred Drake <fdrake@acm.org>
parents: 11463
diff changeset
956 See chapters 3 and 7 of the \citetitle[../ref/ref.html]{Python
11463
17e12305973e Use \citetitle and \programopt as appropriate.
Fred Drake <fdrake@acm.org>
parents: 11183
diff changeset
957 Reference Manual} for these.
8730
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
958
10241
f138ba72bf2d Update description of what modules "look like" when printed.
Fred Drake <fdrake@acm.org>
parents: 10156
diff changeset
959
10156
0f7d694bc334 Make sure all HTML pages generated from this section have reasonable
Fred Drake <fdrake@acm.org>
parents: 10147
diff changeset
960 \subsubsection{Functions \label{typesfunctions}}
8730
8a306dfd9f33 Move files around to get the names to match the module names except for
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parents:
diff changeset
961
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
962 Function objects are created by function definitions. The only
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
963 operation on a function object is to call it:
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
964 \code{\var{func}(\var{argument-list})}.
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
965
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
966 There are really two flavors of function objects: built-in functions
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
967 and user-defined functions. Both support the same operation (to call
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
968 the function), but the implementation is different, hence the
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
969 different object types.
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
970
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
971 The implementation adds two special read-only attributes:
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
972 \code{\var{f}.func_code} is a function's \dfn{code
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
973 object}\obindex{code} (see below) and \code{\var{f}.func_globals} is
14520
addaba991077 When referring to namespaces, always say "namespaces" instead of
Fred Drake <fdrake@acm.org>
parents: 14485
diff changeset
974 the dictionary used as the function's global namespace (this is the
8730
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
975 same as \code{\var{m}.__dict__} where \var{m} is the module in which
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
976 the function \var{f} was defined).
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
977
15892
8ef31a039a96 Document function attributes for both the function type and the method
Barry Warsaw <barry@python.org>
parents: 15789
diff changeset
978 Function objects also support getting and setting arbitrary
8ef31a039a96 Document function attributes for both the function type and the method
Barry Warsaw <barry@python.org>
parents: 15789
diff changeset
979 attributes, which can be used to, e.g. attach metadata to functions.
8ef31a039a96 Document function attributes for both the function type and the method
Barry Warsaw <barry@python.org>
parents: 15789
diff changeset
980 Regular attribute dot-notation is used to get and set such
8ef31a039a96 Document function attributes for both the function type and the method
Barry Warsaw <barry@python.org>
parents: 15789
diff changeset
981 attributes. \emph{Note that the current implementation only supports
8ef31a039a96 Document function attributes for both the function type and the method
Barry Warsaw <barry@python.org>
parents: 15789
diff changeset
982 function attributes on functions written in Python. Function
8ef31a039a96 Document function attributes for both the function type and the method
Barry Warsaw <barry@python.org>
parents: 15789
diff changeset
983 attributes on built-ins may be supported in the future.}
8ef31a039a96 Document function attributes for both the function type and the method
Barry Warsaw <barry@python.org>
parents: 15789
diff changeset
984
16778
68bd96e426e3 Updates to the semantics of function and method attributes.
Barry Warsaw <barry@python.org>
parents: 16285
diff changeset
985 Functions have another special attribute \code{\var{f}.__dict__}
68bd96e426e3 Updates to the semantics of function and method attributes.
Barry Warsaw <barry@python.org>
parents: 16285
diff changeset
986 (a.k.a. \code{\var{f}.func_dict}) which contains the namespace used to
68bd96e426e3 Updates to the semantics of function and method attributes.
Barry Warsaw <barry@python.org>
parents: 16285
diff changeset
987 support function attributes. \code{__dict__} can be accessed
68bd96e426e3 Updates to the semantics of function and method attributes.
Barry Warsaw <barry@python.org>
parents: 16285
diff changeset
988 directly, set to a dictionary object, or \code{None}. It can also be
68bd96e426e3 Updates to the semantics of function and method attributes.
Barry Warsaw <barry@python.org>
parents: 16285
diff changeset
989 deleted (but the following two lines are equivalent):
68bd96e426e3 Updates to the semantics of function and method attributes.
Barry Warsaw <barry@python.org>
parents: 16285
diff changeset
990
68bd96e426e3 Updates to the semantics of function and method attributes.
Barry Warsaw <barry@python.org>
parents: 16285
diff changeset
991 \begin{verbatim}
68bd96e426e3 Updates to the semantics of function and method attributes.
Barry Warsaw <barry@python.org>
parents: 16285
diff changeset
992 del func.__dict__
68bd96e426e3 Updates to the semantics of function and method attributes.
Barry Warsaw <barry@python.org>
parents: 16285
diff changeset
993 func.__dict__ = None
68bd96e426e3 Updates to the semantics of function and method attributes.
Barry Warsaw <barry@python.org>
parents: 16285
diff changeset
994 \end{verbatim}
8730
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
995
10156
0f7d694bc334 Make sure all HTML pages generated from this section have reasonable
Fred Drake <fdrake@acm.org>
parents: 10147
diff changeset
996 \subsubsection{Methods \label{typesmethods}}
8730
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
997 \obindex{method}
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
998
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
999 Methods are functions that are called using the attribute notation.
9558
fa867d8ee7eb Remove some remaining {\rm ...} constructs.
Fred Drake <fdrake@acm.org>
parents: 9523
diff changeset
1000 There are two flavors: built-in methods (such as \method{append()} on
8730
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1001 lists) and class instance methods. Built-in methods are described
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1002 with the types that support them.
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1003
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1004 The implementation adds two special read-only attributes to class
9034
182c9cbdf053 spoking --> speaking
Fred Drake <fdrake@acm.org>
parents: 8882
diff changeset
1005 instance methods: \code{\var{m}.im_self} is the object on which the
182c9cbdf053 spoking --> speaking
Fred Drake <fdrake@acm.org>
parents: 8882
diff changeset
1006 method operates, and \code{\var{m}.im_func} is the function
182c9cbdf053 spoking --> speaking
Fred Drake <fdrake@acm.org>
parents: 8882
diff changeset
1007 implementing the method. Calling \code{\var{m}(\var{arg-1},
9558
fa867d8ee7eb Remove some remaining {\rm ...} constructs.
Fred Drake <fdrake@acm.org>
parents: 9523
diff changeset
1008 \var{arg-2}, \textrm{\ldots}, \var{arg-n})} is completely equivalent to
9034
182c9cbdf053 spoking --> speaking
Fred Drake <fdrake@acm.org>
parents: 8882
diff changeset
1009 calling \code{\var{m}.im_func(\var{m}.im_self, \var{arg-1},
9558
fa867d8ee7eb Remove some remaining {\rm ...} constructs.
Fred Drake <fdrake@acm.org>
parents: 9523
diff changeset
1010 \var{arg-2}, \textrm{\ldots}, \var{arg-n})}.
8730
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1011
15892
8ef31a039a96 Document function attributes for both the function type and the method
Barry Warsaw <barry@python.org>
parents: 15789
diff changeset
1012 Class instance methods are either \emph{bound} or \emph{unbound},
8ef31a039a96 Document function attributes for both the function type and the method
Barry Warsaw <barry@python.org>
parents: 15789
diff changeset
1013 referring to whether the method was accessed through an instance or a
8ef31a039a96 Document function attributes for both the function type and the method
Barry Warsaw <barry@python.org>
parents: 15789
diff changeset
1014 class, respectively. When a method is unbound, its \code{im_self}
8ef31a039a96 Document function attributes for both the function type and the method
Barry Warsaw <barry@python.org>
parents: 15789
diff changeset
1015 attribute will be \code{None} and if called, an explicit \code{self}
8ef31a039a96 Document function attributes for both the function type and the method
Barry Warsaw <barry@python.org>
parents: 15789
diff changeset
1016 object must be passed as the first argument. In this case,
8ef31a039a96 Document function attributes for both the function type and the method
Barry Warsaw <barry@python.org>
parents: 15789
diff changeset
1017 \code{self} must be an instance of the unbound method's class (or a
8ef31a039a96 Document function attributes for both the function type and the method
Barry Warsaw <barry@python.org>
parents: 15789
diff changeset
1018 subclass of that class), otherwise a \code{TypeError} is raised.
8ef31a039a96 Document function attributes for both the function type and the method
Barry Warsaw <barry@python.org>
parents: 15789
diff changeset
1019
16778
68bd96e426e3 Updates to the semantics of function and method attributes.
Barry Warsaw <barry@python.org>
parents: 16285
diff changeset
1020 Like function objects, methods objects support getting
68bd96e426e3 Updates to the semantics of function and method attributes.
Barry Warsaw <barry@python.org>
parents: 16285
diff changeset
1021 arbitrary attributes. However, since method attributes are actually
68bd96e426e3 Updates to the semantics of function and method attributes.
Barry Warsaw <barry@python.org>
parents: 16285
diff changeset
1022 stored on the underlying function object (i.e. \code{meth.im_func}),
68bd96e426e3 Updates to the semantics of function and method attributes.
Barry Warsaw <barry@python.org>
parents: 16285
diff changeset
1023 setting method attributes on either bound or unbound methods is
68bd96e426e3 Updates to the semantics of function and method attributes.
Barry Warsaw <barry@python.org>
parents: 16285
diff changeset
1024 disallowed. Attempting to set a method attribute results in a
68bd96e426e3 Updates to the semantics of function and method attributes.
Barry Warsaw <barry@python.org>
parents: 16285
diff changeset
1025 \code{TypeError} being raised. In order to set a method attribute,
68bd96e426e3 Updates to the semantics of function and method attributes.
Barry Warsaw <barry@python.org>
parents: 16285
diff changeset
1026 you need to explicitly set it on the underlying function object:
15892
8ef31a039a96 Document function attributes for both the function type and the method
Barry Warsaw <barry@python.org>
parents: 15789
diff changeset
1027
8ef31a039a96 Document function attributes for both the function type and the method
Barry Warsaw <barry@python.org>
parents: 15789
diff changeset
1028 \begin{verbatim}
8ef31a039a96 Document function attributes for both the function type and the method
Barry Warsaw <barry@python.org>
parents: 15789
diff changeset
1029 class C:
8ef31a039a96 Document function attributes for both the function type and the method
Barry Warsaw <barry@python.org>
parents: 15789
diff changeset
1030 def method(self):
8ef31a039a96 Document function attributes for both the function type and the method
Barry Warsaw <barry@python.org>
parents: 15789
diff changeset
1031 pass
8ef31a039a96 Document function attributes for both the function type and the method
Barry Warsaw <barry@python.org>
parents: 15789
diff changeset
1032
8ef31a039a96 Document function attributes for both the function type and the method
Barry Warsaw <barry@python.org>
parents: 15789
diff changeset
1033 c = C()
16778
68bd96e426e3 Updates to the semantics of function and method attributes.
Barry Warsaw <barry@python.org>
parents: 16285
diff changeset
1034 c.method.im_func.whoami = 'my name is c'
15892
8ef31a039a96 Document function attributes for both the function type and the method
Barry Warsaw <barry@python.org>
parents: 15789
diff changeset
1035 \end{verbatim}
8ef31a039a96 Document function attributes for both the function type and the method
Barry Warsaw <barry@python.org>
parents: 15789
diff changeset
1036
11463
17e12305973e Use \citetitle and \programopt as appropriate.
Fred Drake <fdrake@acm.org>
parents: 11183
diff changeset
1037 See the \citetitle[../ref/ref.html]{Python Reference Manual} for more
17e12305973e Use \citetitle and \programopt as appropriate.
Fred Drake <fdrake@acm.org>
parents: 11183
diff changeset
1038 information.
8730
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1039
9083
bc41e86c938c Markup nits.
Fred Drake <fdrake@acm.org>
parents: 9034
diff changeset
1040
bc41e86c938c Markup nits.
Fred Drake <fdrake@acm.org>
parents: 9034
diff changeset
1041 \subsubsection{Code Objects \label{bltin-code-objects}}
8730
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1042 \obindex{code}
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1043
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1044 Code objects are used by the implementation to represent
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1045 ``pseudo-compiled'' executable Python code such as a function body.
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1046 They differ from function objects because they don't contain a
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1047 reference to their global execution environment. Code objects are
9558
fa867d8ee7eb Remove some remaining {\rm ...} constructs.
Fred Drake <fdrake@acm.org>
parents: 9523
diff changeset
1048 returned by the built-in \function{compile()} function and can be
fa867d8ee7eb Remove some remaining {\rm ...} constructs.
Fred Drake <fdrake@acm.org>
parents: 9523
diff changeset
1049 extracted from function objects through their \member{func_code}
8730
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1050 attribute.
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1051 \bifuncindex{compile}
9523
ed6cacddc6c6 Fix indexing of func_code attribute; this is on a function, not a code
Fred Drake <fdrake@acm.org>
parents: 9461
diff changeset
1052 \withsubitem{(function object attribute)}{\ttindex{func_code}}
8730
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1053
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1054 A code object can be executed or evaluated by passing it (instead of a
9558
fa867d8ee7eb Remove some remaining {\rm ...} constructs.
Fred Drake <fdrake@acm.org>
parents: 9523
diff changeset
1055 source string) to the \keyword{exec} statement or the built-in
fa867d8ee7eb Remove some remaining {\rm ...} constructs.
Fred Drake <fdrake@acm.org>
parents: 9523
diff changeset
1056 \function{eval()} function.
8730
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1057 \stindex{exec}
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1058 \bifuncindex{eval}
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1059
11463
17e12305973e Use \citetitle and \programopt as appropriate.
Fred Drake <fdrake@acm.org>
parents: 11183
diff changeset
1060 See the \citetitle[../ref/ref.html]{Python Reference Manual} for more
17e12305973e Use \citetitle and \programopt as appropriate.
Fred Drake <fdrake@acm.org>
parents: 11183
diff changeset
1061 information.
8730
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1062
9083
bc41e86c938c Markup nits.
Fred Drake <fdrake@acm.org>
parents: 9034
diff changeset
1063
bc41e86c938c Markup nits.
Fred Drake <fdrake@acm.org>
parents: 9034
diff changeset
1064 \subsubsection{Type Objects \label{bltin-type-objects}}
8730
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1065
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1066 Type objects represent the various object types. An object's type is
9558
fa867d8ee7eb Remove some remaining {\rm ...} constructs.
Fred Drake <fdrake@acm.org>
parents: 9523
diff changeset
1067 accessed by the built-in function \function{type()}. There are no special
fa867d8ee7eb Remove some remaining {\rm ...} constructs.
Fred Drake <fdrake@acm.org>
parents: 9523
diff changeset
1068 operations on types. The standard module \module{types} defines names
8730
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1069 for all standard built-in types.
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1070 \bifuncindex{type}
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1071 \refstmodindex{types}
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1072
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1073 Types are written like this: \code{<type 'int'>}.
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1074
9083
bc41e86c938c Markup nits.
Fred Drake <fdrake@acm.org>
parents: 9034
diff changeset
1075
bc41e86c938c Markup nits.
Fred Drake <fdrake@acm.org>
parents: 9034
diff changeset
1076 \subsubsection{The Null Object \label{bltin-null-object}}
8730
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1077
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1078 This object is returned by functions that don't explicitly return a
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1079 value. It supports no special operations. There is exactly one null
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1080 object, named \code{None} (a built-in name).
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1081
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1082 It is written as \code{None}.
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1083
9083
bc41e86c938c Markup nits.
Fred Drake <fdrake@acm.org>
parents: 9034
diff changeset
1084
bc41e86c938c Markup nits.
Fred Drake <fdrake@acm.org>
parents: 9034
diff changeset
1085 \subsubsection{The Ellipsis Object \label{bltin-ellipsis-object}}
8734
ddaac06ec326 Document Ellipsis (not much of a documentation snippet, but at least
Guido van Rossum <guido@python.org>
parents: 8730
diff changeset
1086
11463
17e12305973e Use \citetitle and \programopt as appropriate.
Fred Drake <fdrake@acm.org>
parents: 11183
diff changeset
1087 This object is used by extended slice notation (see the
17e12305973e Use \citetitle and \programopt as appropriate.
Fred Drake <fdrake@acm.org>
parents: 11183
diff changeset
1088 \citetitle[../ref/ref.html]{Python Reference Manual}). It supports no
17e12305973e Use \citetitle and \programopt as appropriate.
Fred Drake <fdrake@acm.org>
parents: 11183
diff changeset
1089 special operations. There is exactly one ellipsis object, named
17e12305973e Use \citetitle and \programopt as appropriate.
Fred Drake <fdrake@acm.org>
parents: 11183
diff changeset
1090 \constant{Ellipsis} (a built-in name).
8734
ddaac06ec326 Document Ellipsis (not much of a documentation snippet, but at least
Guido van Rossum <guido@python.org>
parents: 8730
diff changeset
1091
ddaac06ec326 Document Ellipsis (not much of a documentation snippet, but at least
Guido van Rossum <guido@python.org>
parents: 8730
diff changeset
1092 It is written as \code{Ellipsis}.
ddaac06ec326 Document Ellipsis (not much of a documentation snippet, but at least
Guido van Rossum <guido@python.org>
parents: 8730
diff changeset
1093
15383
eeb7c8a5b79f Document the proper exception to be raised by I/O operations on closed
Fred Drake <fdrake@acm.org>
parents: 15332
diff changeset
1094
10636
9fd29021d147 Added index entry for "file objects"; this is appearantly referenced
Fred Drake <fdrake@acm.org>
parents: 10606
diff changeset
1095 \subsubsection{File Objects\obindex{file}
9fd29021d147 Added index entry for "file objects"; this is appearantly referenced
Fred Drake <fdrake@acm.org>
parents: 10606
diff changeset
1096 \label{bltin-file-objects}}
8730
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1097
13933
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
Fred Drake <fdrake@acm.org>
parents: 13894
diff changeset
1098 File objects are implemented using C's \code{stdio} package and can be
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
Fred Drake <fdrake@acm.org>
parents: 13894
diff changeset
1099 created with the built-in function
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
Fred Drake <fdrake@acm.org>
parents: 13894
diff changeset
1100 \function{open()}\bifuncindex{open} described in section
9461
9ffd604807c2 Don't describe something as "below"; that won't make sense for the
Fred Drake <fdrake@acm.org>
parents: 9318
diff changeset
1101 \ref{built-in-funcs}, ``Built-in Functions.'' They are also returned
9ffd604807c2 Don't describe something as "below"; that won't make sense for the
Fred Drake <fdrake@acm.org>
parents: 9318
diff changeset
1102 by some other built-in functions and methods, e.g.,
13933
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
Fred Drake <fdrake@acm.org>
parents: 13894
diff changeset
1103 \function{os.popen()} and \function{os.fdopen()} and the
9461
9ffd604807c2 Don't describe something as "below"; that won't make sense for the
Fred Drake <fdrake@acm.org>
parents: 9318
diff changeset
1104 \method{makefile()} method of socket objects.
13933
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
Fred Drake <fdrake@acm.org>
parents: 13894
diff changeset
1105 \refstmodindex{os}
8730
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1106 \refbimodindex{socket}
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1107
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1108 When a file operation fails for an I/O-related reason, the exception
9558
fa867d8ee7eb Remove some remaining {\rm ...} constructs.
Fred Drake <fdrake@acm.org>
parents: 9523
diff changeset
1109 \exception{IOError} is raised. This includes situations where the
fa867d8ee7eb Remove some remaining {\rm ...} constructs.
Fred Drake <fdrake@acm.org>
parents: 9523
diff changeset
1110 operation is not defined for some reason, like \method{seek()} on a tty
8730
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1111 device or writing a file opened for reading.
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1112
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1113 Files have the following methods:
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1114
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1115
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1116 \begin{methoddesc}[file]{close}{}
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1117 Close the file. A closed file cannot be read or written anymore.
15383
eeb7c8a5b79f Document the proper exception to be raised by I/O operations on closed
Fred Drake <fdrake@acm.org>
parents: 15332
diff changeset
1118 Any operation which requires that the file be open will raise a
eeb7c8a5b79f Document the proper exception to be raised by I/O operations on closed
Fred Drake <fdrake@acm.org>
parents: 15332
diff changeset
1119 \exception{ValueError} after the file has been closed. Calling
14685
faf3e734254d Clarify a number of issues about the file-like object API based on
Fred Drake <fdrake@acm.org>
parents: 14557
diff changeset
1120 \method{close()} more than once is allowed.
8730
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1121 \end{methoddesc}
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1122
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1123 \begin{methoddesc}[file]{flush}{}
14685
faf3e734254d Clarify a number of issues about the file-like object API based on
Fred Drake <fdrake@acm.org>
parents: 14557
diff changeset
1124 Flush the internal buffer, like \code{stdio}'s
faf3e734254d Clarify a number of issues about the file-like object API based on
Fred Drake <fdrake@acm.org>
parents: 14557
diff changeset
1125 \cfunction{fflush()}. This may be a no-op on some file-like
faf3e734254d Clarify a number of issues about the file-like object API based on
Fred Drake <fdrake@acm.org>
parents: 14557
diff changeset
1126 objects.
8730
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1127 \end{methoddesc}
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1128
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1129 \begin{methoddesc}[file]{isatty}{}
14685
faf3e734254d Clarify a number of issues about the file-like object API based on
Fred Drake <fdrake@acm.org>
parents: 14557
diff changeset
1130 Return true if the file is connected to a tty(-like) device, else
faf3e734254d Clarify a number of issues about the file-like object API based on
Fred Drake <fdrake@acm.org>
parents: 14557
diff changeset
1131 false. \strong{Note:} If a file-like object is not associated
faf3e734254d Clarify a number of issues about the file-like object API based on
Fred Drake <fdrake@acm.org>
parents: 14557
diff changeset
1132 with a real file, this method should \emph{not} be implemented.
8730
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1133 \end{methoddesc}
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1134
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1135 \begin{methoddesc}[file]{fileno}{}
14685
faf3e734254d Clarify a number of issues about the file-like object API based on
Fred Drake <fdrake@acm.org>
parents: 14557
diff changeset
1136 \index{file descriptor}
faf3e734254d Clarify a number of issues about the file-like object API based on
Fred Drake <fdrake@acm.org>
parents: 14557
diff changeset
1137 \index{descriptor, file}
faf3e734254d Clarify a number of issues about the file-like object API based on
Fred Drake <fdrake@acm.org>
parents: 14557
diff changeset
1138 Return the integer ``file descriptor'' that is used by the
faf3e734254d Clarify a number of issues about the file-like object API based on
Fred Drake <fdrake@acm.org>
parents: 14557
diff changeset
1139 underlying implementation to request I/O operations from the
faf3e734254d Clarify a number of issues about the file-like object API based on
Fred Drake <fdrake@acm.org>
parents: 14557
diff changeset
1140 operating system. This can be useful for other, lower level
faf3e734254d Clarify a number of issues about the file-like object API based on
Fred Drake <fdrake@acm.org>
parents: 14557
diff changeset
1141 interfaces that use file descriptors, e.g.\ module
faf3e734254d Clarify a number of issues about the file-like object API based on
Fred Drake <fdrake@acm.org>
parents: 14557
diff changeset
1142 \refmodule{fcntl}\refbimodindex{fcntl} or \function{os.read()} and
faf3e734254d Clarify a number of issues about the file-like object API based on
Fred Drake <fdrake@acm.org>
parents: 14557
diff changeset
1143 friends. \strong{Note:} File-like objects which do not have a real
faf3e734254d Clarify a number of issues about the file-like object API based on
Fred Drake <fdrake@acm.org>
parents: 14557
diff changeset
1144 file descriptor should \emph{not} provide this method!
8730
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1145 \end{methoddesc}
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1146
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1147 \begin{methoddesc}[file]{read}{\optional{size}}
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1148 Read at most \var{size} bytes from the file (less if the read hits
10606
fe5fcb7e73f7 Correct documentation for <file>.read(); Python makes a serious
Fred Drake <fdrake@acm.org>
parents: 10520
diff changeset
1149 \EOF{} before obtaining \var{size} bytes). If the \var{size}
fe5fcb7e73f7 Correct documentation for <file>.read(); Python makes a serious
Fred Drake <fdrake@acm.org>
parents: 10520
diff changeset
1150 argument is negative or omitted, read all data until \EOF{} is
fe5fcb7e73f7 Correct documentation for <file>.read(); Python makes a serious
Fred Drake <fdrake@acm.org>
parents: 10520
diff changeset
1151 reached. The bytes are returned as a string object. An empty
fe5fcb7e73f7 Correct documentation for <file>.read(); Python makes a serious
Fred Drake <fdrake@acm.org>
parents: 10520
diff changeset
1152 string is returned when \EOF{} is encountered immediately. (For
fe5fcb7e73f7 Correct documentation for <file>.read(); Python makes a serious
Fred Drake <fdrake@acm.org>
parents: 10520
diff changeset
1153 certain files, like ttys, it makes sense to continue reading after
fe5fcb7e73f7 Correct documentation for <file>.read(); Python makes a serious
Fred Drake <fdrake@acm.org>
parents: 10520
diff changeset
1154 an \EOF{} is hit.) Note that this method may call the underlying
fe5fcb7e73f7 Correct documentation for <file>.read(); Python makes a serious
Fred Drake <fdrake@acm.org>
parents: 10520
diff changeset
1155 C function \cfunction{fread()} more than once in an effort to
fe5fcb7e73f7 Correct documentation for <file>.read(); Python makes a serious
Fred Drake <fdrake@acm.org>
parents: 10520
diff changeset
1156 acquire as close to \var{size} bytes as possible.
8730
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1157 \end{methoddesc}
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1158
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1159 \begin{methoddesc}[file]{readline}{\optional{size}}
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1160 Read one entire line from the file. A trailing newline character is
10520
7ee1e3134147 Fixed latex2html weirdness with footnotes.
Fred Drake <fdrake@acm.org>
parents: 10241
diff changeset
1161 kept in the string\footnote{
7ee1e3134147 Fixed latex2html weirdness with footnotes.
Fred Drake <fdrake@acm.org>
parents: 10241
diff changeset
1162 The advantage of leaving the newline on is that an empty string
8730
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1163 can be returned to mean \EOF{} without being ambiguous. Another
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1164 advantage is that (in cases where it might matter, e.g. if you
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1165 want to make an exact copy of a file while scanning its lines)
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1166 you can tell whether the last line of a file ended in a newline
13933
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
Fred Drake <fdrake@acm.org>
parents: 13894
diff changeset
1167 or not (yes this happens!).
4d14eef8ea07 Added Marc-Andre Lemburg's documentation for string methods, with some
Fred Drake <fdrake@acm.org>
parents: 13894
diff changeset
1168 } (but may be absent when a file ends with an
8730
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1169 incomplete line). If the \var{size} argument is present and
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1170 non-negative, it is a maximum byte count (including the trailing
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1171 newline) and an incomplete line may be returned.
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1172 An empty string is returned when \EOF{} is hit
14685
faf3e734254d Clarify a number of issues about the file-like object API based on
Fred Drake <fdrake@acm.org>
parents: 14557
diff changeset
1173 immediately. Note: Unlike \code{stdio}'s \cfunction{fgets()}, the
faf3e734254d Clarify a number of issues about the file-like object API based on
Fred Drake <fdrake@acm.org>
parents: 14557
diff changeset
1174 returned string contains null characters (\code{'\e 0'}) if they
faf3e734254d Clarify a number of issues about the file-like object API based on
Fred Drake <fdrake@acm.org>
parents: 14557
diff changeset
1175 occurred in the input.
8730
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1176 \end{methoddesc}
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1177
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1178 \begin{methoddesc}[file]{readlines}{\optional{sizehint}}
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1179 Read until \EOF{} using \method{readline()} and return a list containing
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1180 the lines thus read. If the optional \var{sizehint} argument is
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1181 present, instead of reading up to \EOF{}, whole lines totalling
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1182 approximately \var{sizehint} bytes (possibly after rounding up to an
14685
faf3e734254d Clarify a number of issues about the file-like object API based on
Fred Drake <fdrake@acm.org>
parents: 14557
diff changeset
1183 internal buffer size) are read. Objects implementing a file-like
faf3e734254d Clarify a number of issues about the file-like object API based on
Fred Drake <fdrake@acm.org>
parents: 14557
diff changeset
1184 interface may choose to ignore \var{sizehint} if it cannot be
faf3e734254d Clarify a number of issues about the file-like object API based on
Fred Drake <fdrake@acm.org>
parents: 14557
diff changeset
1185 implemented, or cannot be implemented efficiently.
8730
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1186 \end{methoddesc}
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1187
15926
ac13cef423c8 Document xreadlines() method. (Forgot to check this in before!)
Guido van Rossum <guido@python.org>
parents: 15896
diff changeset
1188 \begin{methoddesc}[file]{xreadlines}{}
ac13cef423c8 Document xreadlines() method. (Forgot to check this in before!)
Guido van Rossum <guido@python.org>
parents: 15896
diff changeset
1189 Equivalent to \function{xreadlines.xreadlines(file)}.\refstmodindex{xreadlines}
ac13cef423c8 Document xreadlines() method. (Forgot to check this in before!)
Guido van Rossum <guido@python.org>
parents: 15896
diff changeset
1190 \end{methoddesc}
ac13cef423c8 Document xreadlines() method. (Forgot to check this in before!)
Guido van Rossum <guido@python.org>
parents: 15896
diff changeset
1191
8730
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1192 \begin{methoddesc}[file]{seek}{offset\optional{, whence}}
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1193 Set the file's current position, like \code{stdio}'s \cfunction{fseek()}.
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1194 The \var{whence} argument is optional and defaults to \code{0}
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1195 (absolute file positioning); other values are \code{1} (seek
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1196 relative to the current position) and \code{2} (seek relative to the
15731
a06415994cb5 Added information about the interaction of opening a file in append mode
Fred Drake <fdrake@acm.org>
parents: 15522
diff changeset
1197 file's end). There is no return value. Note that if the file is
a06415994cb5 Added information about the interaction of opening a file in append mode
Fred Drake <fdrake@acm.org>
parents: 15522
diff changeset
1198 opened for appending (mode \code{'a'} or \code{'a+'}), any
a06415994cb5 Added information about the interaction of opening a file in append mode
Fred Drake <fdrake@acm.org>
parents: 15522
diff changeset
1199 \method{seek()} operations will be undone at the next write. If the
a06415994cb5 Added information about the interaction of opening a file in append mode
Fred Drake <fdrake@acm.org>
parents: 15522
diff changeset
1200 file is only opened for writing in append mode (mode \code{'a'}),
a06415994cb5 Added information about the interaction of opening a file in append mode
Fred Drake <fdrake@acm.org>
parents: 15522
diff changeset
1201 this method is essentially a no-op, but it remains useful for files
a06415994cb5 Added information about the interaction of opening a file in append mode
Fred Drake <fdrake@acm.org>
parents: 15522
diff changeset
1202 opened in append mode with reading enabled (mode \code{'a+'}).
8730
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1203 \end{methoddesc}
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1204
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1205 \begin{methoddesc}[file]{tell}{}
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1206 Return the file's current position, like \code{stdio}'s
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1207 \cfunction{ftell()}.
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1208 \end{methoddesc}
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1209
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1210 \begin{methoddesc}[file]{truncate}{\optional{size}}
14685
faf3e734254d Clarify a number of issues about the file-like object API based on
Fred Drake <fdrake@acm.org>
parents: 14557
diff changeset
1211 Truncate the file's size. If the optional \var{size} argument
faf3e734254d Clarify a number of issues about the file-like object API based on
Fred Drake <fdrake@acm.org>
parents: 14557
diff changeset
1212 present, the file is truncated to (at most) that size. The size
faf3e734254d Clarify a number of issues about the file-like object API based on
Fred Drake <fdrake@acm.org>
parents: 14557
diff changeset
1213 defaults to the current position. Availability of this function
faf3e734254d Clarify a number of issues about the file-like object API based on
Fred Drake <fdrake@acm.org>
parents: 14557
diff changeset
1214 depends on the operating system version (for example, not all
faf3e734254d Clarify a number of issues about the file-like object API based on
Fred Drake <fdrake@acm.org>
parents: 14557
diff changeset
1215 \UNIX{} versions support this operation).
8730
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1216 \end{methoddesc}
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1217
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1218 \begin{methoddesc}[file]{write}{str}
15789
9e9556924b0a Added documentation for the xreadlines module & related changes. The
Fred Drake <fdrake@acm.org>
parents: 15731
diff changeset
1219 Write a string to the file. There is no return value. Note: Due to
9e9556924b0a Added documentation for the xreadlines module & related changes. The
Fred Drake <fdrake@acm.org>
parents: 15731
diff changeset
1220 buffering, the string may not actually show up in the file until
9e9556924b0a Added documentation for the xreadlines module & related changes. The
Fred Drake <fdrake@acm.org>
parents: 15731
diff changeset
1221 the \method{flush()} or \method{close()} method is called.
8730
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1222 \end{methoddesc}
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1223
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1224 \begin{methoddesc}[file]{writelines}{list}
15789
9e9556924b0a Added documentation for the xreadlines module & related changes. The
Fred Drake <fdrake@acm.org>
parents: 15731
diff changeset
1225 Write a list of strings to the file. There is no return value.
9e9556924b0a Added documentation for the xreadlines module & related changes. The
Fred Drake <fdrake@acm.org>
parents: 15731
diff changeset
1226 (The name is intended to match \method{readlines()};
9e9556924b0a Added documentation for the xreadlines module & related changes. The
Fred Drake <fdrake@acm.org>
parents: 15731
diff changeset
1227 \method{writelines()} does not add line separators.)
9e9556924b0a Added documentation for the xreadlines module & related changes. The
Fred Drake <fdrake@acm.org>
parents: 15731
diff changeset
1228 \end{methoddesc}
9e9556924b0a Added documentation for the xreadlines module & related changes. The
Fred Drake <fdrake@acm.org>
parents: 15731
diff changeset
1229
9e9556924b0a Added documentation for the xreadlines module & related changes. The
Fred Drake <fdrake@acm.org>
parents: 15731
diff changeset
1230 \begin{methoddesc}[file]{xreadlines}{}
9e9556924b0a Added documentation for the xreadlines module & related changes. The
Fred Drake <fdrake@acm.org>
parents: 15731
diff changeset
1231 Equivalent to
9e9556924b0a Added documentation for the xreadlines module & related changes. The
Fred Drake <fdrake@acm.org>
parents: 15731
diff changeset
1232 \function{xreadlines.xreadlines(\var{file})}.\refstmodindex{xreadlines}
9e9556924b0a Added documentation for the xreadlines module & related changes. The
Fred Drake <fdrake@acm.org>
parents: 15731
diff changeset
1233 (See the \refmodule{xreadlines} module for more information.)
8730
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1234 \end{methoddesc}
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1235
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1236
14685
faf3e734254d Clarify a number of issues about the file-like object API based on
Fred Drake <fdrake@acm.org>
parents: 14557
diff changeset
1237 File objects also offer a number of other interesting attributes.
faf3e734254d Clarify a number of issues about the file-like object API based on
Fred Drake <fdrake@acm.org>
parents: 14557
diff changeset
1238 These are not required for file-like objects, but should be
faf3e734254d Clarify a number of issues about the file-like object API based on
Fred Drake <fdrake@acm.org>
parents: 14557
diff changeset
1239 implemented if they make sense for the particular object.
8730
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1240
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1241 \begin{memberdesc}[file]{closed}
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1242 Boolean indicating the current state of the file object. This is a
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1243 read-only attribute; the \method{close()} method changes the value.
14685
faf3e734254d Clarify a number of issues about the file-like object API based on
Fred Drake <fdrake@acm.org>
parents: 14557
diff changeset
1244 It may not be available on all file-like objects.
8730
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1245 \end{memberdesc}
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1246
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1247 \begin{memberdesc}[file]{mode}
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1248 The I/O mode for the file. If the file was created using the
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1249 \function{open()} built-in function, this will be the value of the
14685
faf3e734254d Clarify a number of issues about the file-like object API based on
Fred Drake <fdrake@acm.org>
parents: 14557
diff changeset
1250 \var{mode} parameter. This is a read-only attribute and may not be
faf3e734254d Clarify a number of issues about the file-like object API based on
Fred Drake <fdrake@acm.org>
parents: 14557
diff changeset
1251 present on all file-like objects.
8730
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1252 \end{memberdesc}
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1253
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1254 \begin{memberdesc}[file]{name}
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1255 If the file object was created using \function{open()}, the name of
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1256 the file. Otherwise, some string that indicates the source of the
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1257 file object, of the form \samp{<\mbox{\ldots}>}. This is a read-only
14685
faf3e734254d Clarify a number of issues about the file-like object API based on
Fred Drake <fdrake@acm.org>
parents: 14557
diff changeset
1258 attribute and may not be present on all file-like objects.
8730
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1259 \end{memberdesc}
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1260
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1261 \begin{memberdesc}[file]{softspace}
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1262 Boolean that indicates whether a space character needs to be printed
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1263 before another value when using the \keyword{print} statement.
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1264 Classes that are trying to simulate a file object should also have a
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1265 writable \member{softspace} attribute, which should be initialized to
14485
ac0246586d52 Improve a couple of references to the language reference, making them
Fred Drake <fdrake@acm.org>
parents: 14044
diff changeset
1266 zero. This will be automatic for most classes implemented in Python
ac0246586d52 Improve a couple of references to the language reference, making them
Fred Drake <fdrake@acm.org>
parents: 14044
diff changeset
1267 (care may be needed for objects that override attribute access); types
ac0246586d52 Improve a couple of references to the language reference, making them
Fred Drake <fdrake@acm.org>
parents: 14044
diff changeset
1268 implemented in C will have to provide a writable
ac0246586d52 Improve a couple of references to the language reference, making them
Fred Drake <fdrake@acm.org>
parents: 14044
diff changeset
1269 \member{softspace} attribute.
14705
4712f5b8f279 Clarify that the softspace attribute is used by print for state management,
Fred Drake <fdrake@acm.org>
parents: 14685
diff changeset
1270 \strong{Note:} This attribute is not used to control the
4712f5b8f279 Clarify that the softspace attribute is used by print for state management,
Fred Drake <fdrake@acm.org>
parents: 14685
diff changeset
1271 \keyword{print} statement, but to allow the implementation of
4712f5b8f279 Clarify that the softspace attribute is used by print for state management,
Fred Drake <fdrake@acm.org>
parents: 14685
diff changeset
1272 \keyword{print} to keep track of its internal state.
8730
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1273 \end{memberdesc}
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1274
15383
eeb7c8a5b79f Document the proper exception to be raised by I/O operations on closed
Fred Drake <fdrake@acm.org>
parents: 15332
diff changeset
1275
10156
0f7d694bc334 Make sure all HTML pages generated from this section have reasonable
Fred Drake <fdrake@acm.org>
parents: 10147
diff changeset
1276 \subsubsection{Internal Objects \label{typesinternal}}
8730
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1277
11463
17e12305973e Use \citetitle and \programopt as appropriate.
Fred Drake <fdrake@acm.org>
parents: 11183
diff changeset
1278 See the \citetitle[../ref/ref.html]{Python Reference Manual} for this
14044
a905c5aa0691 As pointed out by Denis S. Otkidach <den@analyt.chem.msu.ru>, xrange()
Fred Drake <fdrake@acm.org>
parents: 13967
diff changeset
1279 information. It describes stack frame objects, traceback objects, and
a905c5aa0691 As pointed out by Denis S. Otkidach <den@analyt.chem.msu.ru>, xrange()
Fred Drake <fdrake@acm.org>
parents: 13967
diff changeset
1280 slice objects.
8730
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1281
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1282
9083
bc41e86c938c Markup nits.
Fred Drake <fdrake@acm.org>
parents: 9034
diff changeset
1283 \subsection{Special Attributes \label{specialattrs}}
8730
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1284
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1285 The implementation adds a few special read-only attributes to several
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1286 object types, where they are relevant:
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1287
15383
eeb7c8a5b79f Document the proper exception to be raised by I/O operations on closed
Fred Drake <fdrake@acm.org>
parents: 15332
diff changeset
1288 \begin{memberdesc}[object]{__dict__}
eeb7c8a5b79f Document the proper exception to be raised by I/O operations on closed
Fred Drake <fdrake@acm.org>
parents: 15332
diff changeset
1289 A dictionary or other mapping object used to store an
9083
bc41e86c938c Markup nits.
Fred Drake <fdrake@acm.org>
parents: 9034
diff changeset
1290 object's (writable) attributes.
15383
eeb7c8a5b79f Document the proper exception to be raised by I/O operations on closed
Fred Drake <fdrake@acm.org>
parents: 15332
diff changeset
1291 \end{memberdesc}
8730
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1292
15383
eeb7c8a5b79f Document the proper exception to be raised by I/O operations on closed
Fred Drake <fdrake@acm.org>
parents: 15332
diff changeset
1293 \begin{memberdesc}[object]{__methods__}
9083
bc41e86c938c Markup nits.
Fred Drake <fdrake@acm.org>
parents: 9034
diff changeset
1294 List of the methods of many built-in object types,
8730
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1295 e.g., \code{[].__methods__} yields
9083
bc41e86c938c Markup nits.
Fred Drake <fdrake@acm.org>
parents: 9034
diff changeset
1296 \code{['append', 'count', 'index', 'insert', 'pop', 'remove',
15383
eeb7c8a5b79f Document the proper exception to be raised by I/O operations on closed
Fred Drake <fdrake@acm.org>
parents: 15332
diff changeset
1297 'reverse', 'sort']}. This usually does not need to be explicitly
eeb7c8a5b79f Document the proper exception to be raised by I/O operations on closed
Fred Drake <fdrake@acm.org>
parents: 15332
diff changeset
1298 provided by the object.
eeb7c8a5b79f Document the proper exception to be raised by I/O operations on closed
Fred Drake <fdrake@acm.org>
parents: 15332
diff changeset
1299 \end{memberdesc}
8730
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1300
15383
eeb7c8a5b79f Document the proper exception to be raised by I/O operations on closed
Fred Drake <fdrake@acm.org>
parents: 15332
diff changeset
1301 \begin{memberdesc}[object]{__members__}
eeb7c8a5b79f Document the proper exception to be raised by I/O operations on closed
Fred Drake <fdrake@acm.org>
parents: 15332
diff changeset
1302 Similar to \member{__methods__}, but lists data attributes. This
eeb7c8a5b79f Document the proper exception to be raised by I/O operations on closed
Fred Drake <fdrake@acm.org>
parents: 15332
diff changeset
1303 usually does not need to be explicitly provided by the object.
eeb7c8a5b79f Document the proper exception to be raised by I/O operations on closed
Fred Drake <fdrake@acm.org>
parents: 15332
diff changeset
1304 \end{memberdesc}
8730
8a306dfd9f33 Move files around to get the names to match the module names except for
Fred Drake <fdrake@acm.org>
parents:
diff changeset
1305
15383
eeb7c8a5b79f Document the proper exception to be raised by I/O operations on closed
Fred Drake <fdrake@acm.org>
parents: 15332
diff changeset
1306 \begin{memberdesc}[instance]{__class__}
eeb7c8a5b79f Document the proper exception to be raised by I/O operations on closed
Fred Drake <fdrake@acm.org>
parents: 15332
diff changeset
1307 The class to which a class instance belongs.
eeb7c8a5b79f Document the proper exception to be raised by I/O operations on closed
Fred Drake <fdrake@acm.org>
parents: 15332
diff changeset
1308 \end{memberdesc}
eeb7c8a5b79f Document the proper exception to be raised by I/O operations on closed
Fred Drake <fdrake@acm.org>
parents: 15332
diff changeset
1309
eeb7c8a5b79f Document the proper exception to be raised by I/O operations on closed
Fred Drake <fdrake@acm.org>
parents: 15332
diff changeset
1310 \begin{memberdesc}[class]{__bases__}
9083
bc41e86c938c Markup nits.
Fred Drake <fdrake@acm.org>
parents: 9034
diff changeset
1311 The tuple of base classes of a class object.
15383
eeb7c8a5b79f Document the proper exception to be raised by I/O operations on closed
Fred Drake <fdrake@acm.org>
parents: 15332
diff changeset
1312 \end{memberdesc}