cpython-lru_cache-weakref: Doc/lib/libdifflib.tex annotate

annotate Doc/lib/libdifflib.tex @ 33909:2fa872784eb6 legacy-trunk

SF bug #1060825: Error in difflib docs

author	Raymond Hettinger <python@rcn.com>
date	Fri, 05 Nov 2004 16:38:08 +0000
parents	10b25414628c
children	67f2190e1f6d

rev	line source
16682 3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	1 \section{\module{difflib} ---
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	2 Helpers for computing deltas}
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	3
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	4 \declaremodule{standard}{difflib}
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	5 \modulesynopsis{Helpers for computing differences between objects.}
31275 8c13ab69ba4f - update Tim's email address Fred Drake <fdrake@acm.org> parents: 29404 diff changeset	6 \moduleauthor{Tim Peters}{tim_one@users.sourceforge.net}
8c13ab69ba4f - update Tim's email address Fred Drake <fdrake@acm.org> parents: 29404 diff changeset	7 \sectionauthor{Tim Peters}{tim_one@users.sourceforge.net}
16682 3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	8 % LaTeXification by Fred L. Drake, Jr. <fdrake@acm.org>.
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	9
17388 e4abe74bc973 Add note that difflib was added in Python 2.1. Fred Drake <fdrake@acm.org> parents: 17382 diff changeset	10 \versionadded{2.1}
e4abe74bc973 Add note that difflib was added in Python 2.1. Fred Drake <fdrake@acm.org> parents: 17382 diff changeset	11
e4abe74bc973 Add note that difflib was added in Python 2.1. Fred Drake <fdrake@acm.org> parents: 17382 diff changeset	12
19232 65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	13 \begin{classdesc*}{SequenceMatcher}
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	14 This is a flexible class for comparing pairs of sequences of any
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	15 type, so long as the sequence elements are hashable. The basic
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	16 algorithm predates, and is a little fancier than, an algorithm
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	17 published in the late 1980's by Ratcliff and Obershelp under the
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	18 hyperbolic name ``gestalt pattern matching.'' The idea is to find
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	19 the longest contiguous matching subsequence that contains no
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	20 ``junk'' elements (the Ratcliff and Obershelp algorithm doesn't
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	21 address junk). The same idea is then applied recursively to the
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	22 pieces of the sequences to the left and to the right of the matching
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	23 subsequence. This does not yield minimal edit sequences, but does
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	24 tend to yield matches that ``look right'' to people.
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	25
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	26 \strong{Timing:} The basic Ratcliff-Obershelp algorithm is cubic
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	27 time in the worst case and quadratic time in the expected case.
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	28 \class{SequenceMatcher} is quadratic time for the worst case and has
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	29 expected-case behavior dependent in a complicated way on how many
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	30 elements the sequences have in common; best case time is linear.
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	31 \end{classdesc*}
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	32
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	33 \begin{classdesc*}{Differ}
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	34 This is a class for comparing sequences of lines of text, and
20038 8a6f2ee6eaba Make difflib.ndiff() and difflib.Differ.compare() generators. This Tim Peters <tim.peters@gmail.com> parents: 19232 diff changeset	35 producing human-readable differences or deltas. Differ uses
19232 65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	36 \class{SequenceMatcher} both to compare sequences of lines, and to
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	37 compare sequences of characters within similar (near-matching)
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	38 lines.
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	39
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	40 Each line of a \class{Differ} delta begins with a two-letter code:
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	41
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	42 \begin{tableii}{l\|l}{code}{Code}{Meaning}
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	43 \lineii{'- '}{line unique to sequence 1}
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	44 \lineii{'+ '}{line unique to sequence 2}
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	45 \lineii{' '}{line common to both sequences}
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	46 \lineii{'? '}{line not present in either input sequence}
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	47 \end{tableii}
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	48
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	49 Lines beginning with `\code{?~}' attempt to guide the eye to
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	50 intraline differences, and were not present in either input
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	51 sequence. These lines can be confusing if the sequences contain tab
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	52 characters.
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	53 \end{classdesc*}
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	54
33319 6d3bdd19beeb Patch #914575: difflib side by side diff support, diff.py s/b/s HTML option. Martin v. Löwis <martin@v.loewis.de> parents: 31410 diff changeset	55 \begin{classdesc*}{HtmlDiff}
6d3bdd19beeb Patch #914575: difflib side by side diff support, diff.py s/b/s HTML option. Martin v. Löwis <martin@v.loewis.de> parents: 31410 diff changeset	56
6d3bdd19beeb Patch #914575: difflib side by side diff support, diff.py s/b/s HTML option. Martin v. Löwis <martin@v.loewis.de> parents: 31410 diff changeset	57 This class can be used to create an HTML table (or a complete HTML file
33448 5570fae1f01c Typo fix: 'comparisions' is not a word Andrew M. Kuchling <amk@amk.ca> parents: 33319 diff changeset	58 containing the table) showing a side by side, line by line comparison
33462 5876636ca8c6 HtmlDiff corrections from Dan Gass, + trimmed trailing whitespace. Tim Peters <tim.peters@gmail.com> parents: 33448 diff changeset	59 of text with inter-line and intra-line change highlights. The table can
33319 6d3bdd19beeb Patch #914575: difflib side by side diff support, diff.py s/b/s HTML option. Martin v. Löwis <martin@v.loewis.de> parents: 31410 diff changeset	60 be generated in either full or contextual difference mode.
6d3bdd19beeb Patch #914575: difflib side by side diff support, diff.py s/b/s HTML option. Martin v. Löwis <martin@v.loewis.de> parents: 31410 diff changeset	61
6d3bdd19beeb Patch #914575: difflib side by side diff support, diff.py s/b/s HTML option. Martin v. Löwis <martin@v.loewis.de> parents: 31410 diff changeset	62 The constructor for this class is:
6d3bdd19beeb Patch #914575: difflib side by side diff support, diff.py s/b/s HTML option. Martin v. Löwis <martin@v.loewis.de> parents: 31410 diff changeset	63
33754 10b25414628c SF bug 1046690: difflib.HtmlDiff doc errors. Tim Peters <tim.peters@gmail.com> parents: 33462 diff changeset	64 \begin{funcdesc}{__init__}{\optional{tabsize}\optional{,
10b25414628c SF bug 1046690: difflib.HtmlDiff doc errors. Tim Peters <tim.peters@gmail.com> parents: 33462 diff changeset	65 wrapcolumn}\optional{, linejunk}\optional{, charjunk}}
33319 6d3bdd19beeb Patch #914575: difflib side by side diff support, diff.py s/b/s HTML option. Martin v. Löwis <martin@v.loewis.de> parents: 31410 diff changeset	66
33462 5876636ca8c6 HtmlDiff corrections from Dan Gass, + trimmed trailing whitespace. Tim Peters <tim.peters@gmail.com> parents: 33448 diff changeset	67 Initializes instance of \class{HtmlDiff}.
33319 6d3bdd19beeb Patch #914575: difflib side by side diff support, diff.py s/b/s HTML option. Martin v. Löwis <martin@v.loewis.de> parents: 31410 diff changeset	68
33462 5876636ca8c6 HtmlDiff corrections from Dan Gass, + trimmed trailing whitespace. Tim Peters <tim.peters@gmail.com> parents: 33448 diff changeset	69 \var{tabsize} is an optional keyword argument to specify tab stop spacing
33319 6d3bdd19beeb Patch #914575: difflib side by side diff support, diff.py s/b/s HTML option. Martin v. Löwis <martin@v.loewis.de> parents: 31410 diff changeset	70 and defaults to \code{8}.
6d3bdd19beeb Patch #914575: difflib side by side diff support, diff.py s/b/s HTML option. Martin v. Löwis <martin@v.loewis.de> parents: 31410 diff changeset	71
33462 5876636ca8c6 HtmlDiff corrections from Dan Gass, + trimmed trailing whitespace. Tim Peters <tim.peters@gmail.com> parents: 33448 diff changeset	72 \var{wrapcolumn} is an optional keyword to specify column number where
5876636ca8c6 HtmlDiff corrections from Dan Gass, + trimmed trailing whitespace. Tim Peters <tim.peters@gmail.com> parents: 33448 diff changeset	73 lines are broken and wrapped, defaults to \code{None} where lines are not
33319 6d3bdd19beeb Patch #914575: difflib side by side diff support, diff.py s/b/s HTML option. Martin v. Löwis <martin@v.loewis.de> parents: 31410 diff changeset	74 wrapped.
6d3bdd19beeb Patch #914575: difflib side by side diff support, diff.py s/b/s HTML option. Martin v. Löwis <martin@v.loewis.de> parents: 31410 diff changeset	75
33462 5876636ca8c6 HtmlDiff corrections from Dan Gass, + trimmed trailing whitespace. Tim Peters <tim.peters@gmail.com> parents: 33448 diff changeset	76 \var{linejunk} and \var{charjunk} are optional keyword arguments passed
5876636ca8c6 HtmlDiff corrections from Dan Gass, + trimmed trailing whitespace. Tim Peters <tim.peters@gmail.com> parents: 33448 diff changeset	77 into \code{ndiff()} (used by \class{HtmlDiff} to generate the
5876636ca8c6 HtmlDiff corrections from Dan Gass, + trimmed trailing whitespace. Tim Peters <tim.peters@gmail.com> parents: 33448 diff changeset	78 side by side HTML differences). See \code{ndiff()} documentation for
33319 6d3bdd19beeb Patch #914575: difflib side by side diff support, diff.py s/b/s HTML option. Martin v. Löwis <martin@v.loewis.de> parents: 31410 diff changeset	79 argument default values and descriptions.
33462 5876636ca8c6 HtmlDiff corrections from Dan Gass, + trimmed trailing whitespace. Tim Peters <tim.peters@gmail.com> parents: 33448 diff changeset	80
5876636ca8c6 HtmlDiff corrections from Dan Gass, + trimmed trailing whitespace. Tim Peters <tim.peters@gmail.com> parents: 33448 diff changeset	81 \end{funcdesc}
33319 6d3bdd19beeb Patch #914575: difflib side by side diff support, diff.py s/b/s HTML option. Martin v. Löwis <martin@v.loewis.de> parents: 31410 diff changeset	82
6d3bdd19beeb Patch #914575: difflib side by side diff support, diff.py s/b/s HTML option. Martin v. Löwis <martin@v.loewis.de> parents: 31410 diff changeset	83 The following methods are public:
6d3bdd19beeb Patch #914575: difflib side by side diff support, diff.py s/b/s HTML option. Martin v. Löwis <martin@v.loewis.de> parents: 31410 diff changeset	84
6d3bdd19beeb Patch #914575: difflib side by side diff support, diff.py s/b/s HTML option. Martin v. Löwis <martin@v.loewis.de> parents: 31410 diff changeset	85 \begin{funcdesc}{make_file}{fromlines, tolines
33754 10b25414628c SF bug 1046690: difflib.HtmlDiff doc errors. Tim Peters <tim.peters@gmail.com> parents: 33462 diff changeset	86 \optional{, fromdesc}\optional{, todesc}\optional{, context}\optional{,
10b25414628c SF bug 1046690: difflib.HtmlDiff doc errors. Tim Peters <tim.peters@gmail.com> parents: 33462 diff changeset	87 numlines}}
33319 6d3bdd19beeb Patch #914575: difflib side by side diff support, diff.py s/b/s HTML option. Martin v. Löwis <martin@v.loewis.de> parents: 31410 diff changeset	88 Compares \var{fromlines} and \var{tolines} (lists of strings) and returns
6d3bdd19beeb Patch #914575: difflib side by side diff support, diff.py s/b/s HTML option. Martin v. Löwis <martin@v.loewis.de> parents: 31410 diff changeset	89 a string which is a complete HTML file containing a table showing line by
6d3bdd19beeb Patch #914575: difflib side by side diff support, diff.py s/b/s HTML option. Martin v. Löwis <martin@v.loewis.de> parents: 31410 diff changeset	90 line differences with inter-line and intra-line changes highlighted.
33462 5876636ca8c6 HtmlDiff corrections from Dan Gass, + trimmed trailing whitespace. Tim Peters <tim.peters@gmail.com> parents: 33448 diff changeset	91
5876636ca8c6 HtmlDiff corrections from Dan Gass, + trimmed trailing whitespace. Tim Peters <tim.peters@gmail.com> parents: 33448 diff changeset	92 \var{fromdesc} and \var{todesc} are optional keyword arguments to specify
5876636ca8c6 HtmlDiff corrections from Dan Gass, + trimmed trailing whitespace. Tim Peters <tim.peters@gmail.com> parents: 33448 diff changeset	93 from/to file column header strings (both default to an empty string).
5876636ca8c6 HtmlDiff corrections from Dan Gass, + trimmed trailing whitespace. Tim Peters <tim.peters@gmail.com> parents: 33448 diff changeset	94
33319 6d3bdd19beeb Patch #914575: difflib side by side diff support, diff.py s/b/s HTML option. Martin v. Löwis <martin@v.loewis.de> parents: 31410 diff changeset	95 \var{context} and \var{numlines} are both optional keyword arguments.
33462 5876636ca8c6 HtmlDiff corrections from Dan Gass, + trimmed trailing whitespace. Tim Peters <tim.peters@gmail.com> parents: 33448 diff changeset	96 Set \var{context} to \code{True} when contextual differences are to be
5876636ca8c6 HtmlDiff corrections from Dan Gass, + trimmed trailing whitespace. Tim Peters <tim.peters@gmail.com> parents: 33448 diff changeset	97 shown, else the default is \code{False} to show the full files.
33319 6d3bdd19beeb Patch #914575: difflib side by side diff support, diff.py s/b/s HTML option. Martin v. Löwis <martin@v.loewis.de> parents: 31410 diff changeset	98 \var{numlines} defaults to \code{5}. When \var{context} is \code{True}
33462 5876636ca8c6 HtmlDiff corrections from Dan Gass, + trimmed trailing whitespace. Tim Peters <tim.peters@gmail.com> parents: 33448 diff changeset	99 \var{numlines} controls the number of context lines which surround the
33319 6d3bdd19beeb Patch #914575: difflib side by side diff support, diff.py s/b/s HTML option. Martin v. Löwis <martin@v.loewis.de> parents: 31410 diff changeset	100 difference highlights. When \var{context} is \code{False} \var{numlines}
33462 5876636ca8c6 HtmlDiff corrections from Dan Gass, + trimmed trailing whitespace. Tim Peters <tim.peters@gmail.com> parents: 33448 diff changeset	101 controls the number of lines which are shown before a difference
33319 6d3bdd19beeb Patch #914575: difflib side by side diff support, diff.py s/b/s HTML option. Martin v. Löwis <martin@v.loewis.de> parents: 31410 diff changeset	102 highlight when using the "next" hyperlinks (setting to zero would cause
6d3bdd19beeb Patch #914575: difflib side by side diff support, diff.py s/b/s HTML option. Martin v. Löwis <martin@v.loewis.de> parents: 31410 diff changeset	103 the "next" hyperlinks to place the next difference highlight at the top of
6d3bdd19beeb Patch #914575: difflib side by side diff support, diff.py s/b/s HTML option. Martin v. Löwis <martin@v.loewis.de> parents: 31410 diff changeset	104 the browser without any leading context).
33462 5876636ca8c6 HtmlDiff corrections from Dan Gass, + trimmed trailing whitespace. Tim Peters <tim.peters@gmail.com> parents: 33448 diff changeset	105 \end{funcdesc}
33319 6d3bdd19beeb Patch #914575: difflib side by side diff support, diff.py s/b/s HTML option. Martin v. Löwis <martin@v.loewis.de> parents: 31410 diff changeset	106
6d3bdd19beeb Patch #914575: difflib side by side diff support, diff.py s/b/s HTML option. Martin v. Löwis <martin@v.loewis.de> parents: 31410 diff changeset	107 \begin{funcdesc}{make_table}{fromlines, tolines
33754 10b25414628c SF bug 1046690: difflib.HtmlDiff doc errors. Tim Peters <tim.peters@gmail.com> parents: 33462 diff changeset	108 \optional{, fromdesc}\optional{, todesc}\optional{, context}\optional{,
10b25414628c SF bug 1046690: difflib.HtmlDiff doc errors. Tim Peters <tim.peters@gmail.com> parents: 33462 diff changeset	109 numlines}}
33319 6d3bdd19beeb Patch #914575: difflib side by side diff support, diff.py s/b/s HTML option. Martin v. Löwis <martin@v.loewis.de> parents: 31410 diff changeset	110 Compares \var{fromlines} and \var{tolines} (lists of strings) and returns
6d3bdd19beeb Patch #914575: difflib side by side diff support, diff.py s/b/s HTML option. Martin v. Löwis <martin@v.loewis.de> parents: 31410 diff changeset	111 a string which is a complete HTML table showing line by line differences
6d3bdd19beeb Patch #914575: difflib side by side diff support, diff.py s/b/s HTML option. Martin v. Löwis <martin@v.loewis.de> parents: 31410 diff changeset	112 with inter-line and intra-line changes highlighted.
33462 5876636ca8c6 HtmlDiff corrections from Dan Gass, + trimmed trailing whitespace. Tim Peters <tim.peters@gmail.com> parents: 33448 diff changeset	113
33754 10b25414628c SF bug 1046690: difflib.HtmlDiff doc errors. Tim Peters <tim.peters@gmail.com> parents: 33462 diff changeset	114 The arguments for this method are the same as those for the
10b25414628c SF bug 1046690: difflib.HtmlDiff doc errors. Tim Peters <tim.peters@gmail.com> parents: 33462 diff changeset	115 \method{make_file()} method.
33462 5876636ca8c6 HtmlDiff corrections from Dan Gass, + trimmed trailing whitespace. Tim Peters <tim.peters@gmail.com> parents: 33448 diff changeset	116 \end{funcdesc}
33319 6d3bdd19beeb Patch #914575: difflib side by side diff support, diff.py s/b/s HTML option. Martin v. Löwis <martin@v.loewis.de> parents: 31410 diff changeset	117
33462 5876636ca8c6 HtmlDiff corrections from Dan Gass, + trimmed trailing whitespace. Tim Peters <tim.peters@gmail.com> parents: 33448 diff changeset	118 \file{Tools/scripts/diff.py} is a command-line front-end to this class
33319 6d3bdd19beeb Patch #914575: difflib side by side diff support, diff.py s/b/s HTML option. Martin v. Löwis <martin@v.loewis.de> parents: 31410 diff changeset	119 and contains a good example of its use.
33462 5876636ca8c6 HtmlDiff corrections from Dan Gass, + trimmed trailing whitespace. Tim Peters <tim.peters@gmail.com> parents: 33448 diff changeset	120
5876636ca8c6 HtmlDiff corrections from Dan Gass, + trimmed trailing whitespace. Tim Peters <tim.peters@gmail.com> parents: 33448 diff changeset	121 \versionadded{2.4}
33319 6d3bdd19beeb Patch #914575: difflib side by side diff support, diff.py s/b/s HTML option. Martin v. Löwis <martin@v.loewis.de> parents: 31410 diff changeset	122 \end{classdesc*}
6d3bdd19beeb Patch #914575: difflib side by side diff support, diff.py s/b/s HTML option. Martin v. Löwis <martin@v.loewis.de> parents: 31410 diff changeset	123
33754 10b25414628c SF bug 1046690: difflib.HtmlDiff doc errors. Tim Peters <tim.peters@gmail.com> parents: 33462 diff changeset	124 \begin{funcdesc}{context_diff}{a, b\optional{, fromfile}\optional{,
10b25414628c SF bug 1046690: difflib.HtmlDiff doc errors. Tim Peters <tim.peters@gmail.com> parents: 33462 diff changeset	125 tofile}\optional{, fromfiledate}\optional{, tofiledate}\optional{,
10b25414628c SF bug 1046690: difflib.HtmlDiff doc errors. Tim Peters <tim.peters@gmail.com> parents: 33462 diff changeset	126 n}\optional{, lineterm}}
29398 e6b0a406dc31 Document context_diff() and unified_diff() Raymond Hettinger <python@rcn.com> parents: 26556 diff changeset	127 Compare \var{a} and \var{b} (lists of strings); return a
e6b0a406dc31 Document context_diff() and unified_diff() Raymond Hettinger <python@rcn.com> parents: 26556 diff changeset	128 delta (a generator generating the delta lines) in context diff
e6b0a406dc31 Document context_diff() and unified_diff() Raymond Hettinger <python@rcn.com> parents: 26556 diff changeset	129 format.
33462 5876636ca8c6 HtmlDiff corrections from Dan Gass, + trimmed trailing whitespace. Tim Peters <tim.peters@gmail.com> parents: 33448 diff changeset	130
29398 e6b0a406dc31 Document context_diff() and unified_diff() Raymond Hettinger <python@rcn.com> parents: 26556 diff changeset	131 Context diffs are a compact way of showing just the lines that have
e6b0a406dc31 Document context_diff() and unified_diff() Raymond Hettinger <python@rcn.com> parents: 26556 diff changeset	132 changed plus a few lines of context. The changes are shown in a
e6b0a406dc31 Document context_diff() and unified_diff() Raymond Hettinger <python@rcn.com> parents: 26556 diff changeset	133 before/after style. The number of context lines is set by \var{n}
e6b0a406dc31 Document context_diff() and unified_diff() Raymond Hettinger <python@rcn.com> parents: 26556 diff changeset	134 which defaults to three.
e6b0a406dc31 Document context_diff() and unified_diff() Raymond Hettinger <python@rcn.com> parents: 26556 diff changeset	135
e6b0a406dc31 Document context_diff() and unified_diff() Raymond Hettinger <python@rcn.com> parents: 26556 diff changeset	136 By default, the diff control lines (those with \code{***} or \code{---})
e6b0a406dc31 Document context_diff() and unified_diff() Raymond Hettinger <python@rcn.com> parents: 26556 diff changeset	137 are created with a trailing newline. This is helpful so that inputs created
e6b0a406dc31 Document context_diff() and unified_diff() Raymond Hettinger <python@rcn.com> parents: 26556 diff changeset	138 from \function{file.readlines()} result in diffs that are suitable for use
e6b0a406dc31 Document context_diff() and unified_diff() Raymond Hettinger <python@rcn.com> parents: 26556 diff changeset	139 with \function{file.writelines()} since both the inputs and outputs have
e6b0a406dc31 Document context_diff() and unified_diff() Raymond Hettinger <python@rcn.com> parents: 26556 diff changeset	140 trailing newlines.
e6b0a406dc31 Document context_diff() and unified_diff() Raymond Hettinger <python@rcn.com> parents: 26556 diff changeset	141
e6b0a406dc31 Document context_diff() and unified_diff() Raymond Hettinger <python@rcn.com> parents: 26556 diff changeset	142 For inputs that do not have trailing newlines, set the \var{lineterm}
e6b0a406dc31 Document context_diff() and unified_diff() Raymond Hettinger <python@rcn.com> parents: 26556 diff changeset	143 argument to \code{""} so that the output will be uniformly newline free.
e6b0a406dc31 Document context_diff() and unified_diff() Raymond Hettinger <python@rcn.com> parents: 26556 diff changeset	144
e6b0a406dc31 Document context_diff() and unified_diff() Raymond Hettinger <python@rcn.com> parents: 26556 diff changeset	145 The context diff format normally has a header for filenames and
e6b0a406dc31 Document context_diff() and unified_diff() Raymond Hettinger <python@rcn.com> parents: 26556 diff changeset	146 modification times. Any or all of these may be specified using strings for
e6b0a406dc31 Document context_diff() and unified_diff() Raymond Hettinger <python@rcn.com> parents: 26556 diff changeset	147 \var{fromfile}, \var{tofile}, \var{fromfiledate}, and \var{tofiledate}.
e6b0a406dc31 Document context_diff() and unified_diff() Raymond Hettinger <python@rcn.com> parents: 26556 diff changeset	148 The modification times are normally expressed in the format returned by
e6b0a406dc31 Document context_diff() and unified_diff() Raymond Hettinger <python@rcn.com> parents: 26556 diff changeset	149 \function{time.ctime()}. If not specified, the strings default to blanks.
e6b0a406dc31 Document context_diff() and unified_diff() Raymond Hettinger <python@rcn.com> parents: 26556 diff changeset	150
e6b0a406dc31 Document context_diff() and unified_diff() Raymond Hettinger <python@rcn.com> parents: 26556 diff changeset	151 \file{Tools/scripts/diff.py} is a command-line front-end for this
29404 8c5a6853a02a Add docs for get_grouped_opcodes(). Raymond Hettinger <python@rcn.com> parents: 29398 diff changeset	152 function.
8c5a6853a02a Add docs for get_grouped_opcodes(). Raymond Hettinger <python@rcn.com> parents: 29398 diff changeset	153
8c5a6853a02a Add docs for get_grouped_opcodes(). Raymond Hettinger <python@rcn.com> parents: 29398 diff changeset	154 \versionadded{2.3}
33462 5876636ca8c6 HtmlDiff corrections from Dan Gass, + trimmed trailing whitespace. Tim Peters <tim.peters@gmail.com> parents: 33448 diff changeset	155 \end{funcdesc}
29398 e6b0a406dc31 Document context_diff() and unified_diff() Raymond Hettinger <python@rcn.com> parents: 26556 diff changeset	156
16682 3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	157 \begin{funcdesc}{get_close_matches}{word, possibilities\optional{,
33754 10b25414628c SF bug 1046690: difflib.HtmlDiff doc errors. Tim Peters <tim.peters@gmail.com> parents: 33462 diff changeset	158 n}\optional{, cutoff}}
16682 3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	159 Return a list of the best ``good enough'' matches. \var{word} is a
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	160 sequence for which close matches are desired (typically a string),
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	161 and \var{possibilities} is a list of sequences against which to
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	162 match \var{word} (typically a list of strings).
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	163
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	164 Optional argument \var{n} (default \code{3}) is the maximum number
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	165 of close matches to return; \var{n} must be greater than \code{0}.
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	166
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	167 Optional argument \var{cutoff} (default \code{0.6}) is a float in
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	168 the range [0, 1]. Possibilities that don't score at least that
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	169 similar to \var{word} are ignored.
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	170
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	171 The best (no more than \var{n}) matches among the possibilities are
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	172 returned in a list, sorted by similarity score, most similar first.
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	173
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	174 \begin{verbatim}
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	175 >>> get_close_matches('appel', ['ape', 'apple', 'peach', 'puppy'])
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	176 ['apple', 'ape']
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	177 >>> import keyword
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	178 >>> get_close_matches('wheel', keyword.kwlist)
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	179 ['while']
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	180 >>> get_close_matches('apple', keyword.kwlist)
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	181 []
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	182 >>> get_close_matches('accept', keyword.kwlist)
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	183 ['except']
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	184 \end{verbatim}
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	185 \end{funcdesc}
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	186
33754 10b25414628c SF bug 1046690: difflib.HtmlDiff doc errors. Tim Peters <tim.peters@gmail.com> parents: 33462 diff changeset	187 \begin{funcdesc}{ndiff}{a, b\optional{, linejunk}\optional{, charjunk}}
19232 65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	188 Compare \var{a} and \var{b} (lists of strings); return a
20038 8a6f2ee6eaba Make difflib.ndiff() and difflib.Differ.compare() generators. This Tim Peters <tim.peters@gmail.com> parents: 19232 diff changeset	189 \class{Differ}-style delta (a generator generating the delta lines).
19232 65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	190
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	191 Optional keyword parameters \var{linejunk} and \var{charjunk} are
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	192 for filter functions (or \code{None}):
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	193
23300 b5f6e9f6e7f4 Mostly in SequenceMatcher.{__chain_b, find_longest_match}: Tim Peters <tim.peters@gmail.com> parents: 21106 diff changeset	194 \var{linejunk}: A function that accepts a single string
b5f6e9f6e7f4 Mostly in SequenceMatcher.{__chain_b, find_longest_match}: Tim Peters <tim.peters@gmail.com> parents: 21106 diff changeset	195 argument, and returns true if the string is junk, or false if not.
b5f6e9f6e7f4 Mostly in SequenceMatcher.{__chain_b, find_longest_match}: Tim Peters <tim.peters@gmail.com> parents: 21106 diff changeset	196 The default is (\code{None}), starting with Python 2.3. Before then,
b5f6e9f6e7f4 Mostly in SequenceMatcher.{__chain_b, find_longest_match}: Tim Peters <tim.peters@gmail.com> parents: 21106 diff changeset	197 the default was the module-level function
19232 65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	198 \function{IS_LINE_JUNK()}, which filters out lines without visible
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	199 characters, except for at most one pound character (\character{\#}).
23300 b5f6e9f6e7f4 Mostly in SequenceMatcher.{__chain_b, find_longest_match}: Tim Peters <tim.peters@gmail.com> parents: 21106 diff changeset	200 As of Python 2.3, the underlying \class{SequenceMatcher} class
b5f6e9f6e7f4 Mostly in SequenceMatcher.{__chain_b, find_longest_match}: Tim Peters <tim.peters@gmail.com> parents: 21106 diff changeset	201 does a dynamic analysis of which lines are so frequent as to
b5f6e9f6e7f4 Mostly in SequenceMatcher.{__chain_b, find_longest_match}: Tim Peters <tim.peters@gmail.com> parents: 21106 diff changeset	202 constitute noise, and this usually works better than the pre-2.3
b5f6e9f6e7f4 Mostly in SequenceMatcher.{__chain_b, find_longest_match}: Tim Peters <tim.peters@gmail.com> parents: 21106 diff changeset	203 default.
19232 65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	204
23300 b5f6e9f6e7f4 Mostly in SequenceMatcher.{__chain_b, find_longest_match}: Tim Peters <tim.peters@gmail.com> parents: 21106 diff changeset	205 \var{charjunk}: A function that accepts a character (a string of
b5f6e9f6e7f4 Mostly in SequenceMatcher.{__chain_b, find_longest_match}: Tim Peters <tim.peters@gmail.com> parents: 21106 diff changeset	206 length 1), and returns if the character is junk, or false if not.
19232 65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	207 The default is module-level function \function{IS_CHARACTER_JUNK()},
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	208 which filters out whitespace characters (a blank or tab; note: bad
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	209 idea to include newline in this!).
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	210
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	211 \file{Tools/scripts/ndiff.py} is a command-line front-end to this
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	212 function.
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	213
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	214 \begin{verbatim}
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	215 >>> diff = ndiff('one\ntwo\nthree\n'.splitlines(1),
26556 242ad5c592cc Remove extra ")" in example. Fred Drake <fdrake@acm.org> parents: 23300 diff changeset	216 ... 'ore\ntree\nemu\n'.splitlines(1))
19232 65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	217 >>> print ''.join(diff),
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	218 - one
20038 8a6f2ee6eaba Make difflib.ndiff() and difflib.Differ.compare() generators. This Tim Peters <tim.peters@gmail.com> parents: 19232 diff changeset	219 ? ^
19232 65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	220 + ore
20038 8a6f2ee6eaba Make difflib.ndiff() and difflib.Differ.compare() generators. This Tim Peters <tim.peters@gmail.com> parents: 19232 diff changeset	221 ? ^
19232 65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	222 - two
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	223 - three
20038 8a6f2ee6eaba Make difflib.ndiff() and difflib.Differ.compare() generators. This Tim Peters <tim.peters@gmail.com> parents: 19232 diff changeset	224 ? -
19232 65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	225 + tree
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	226 + emu
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	227 \end{verbatim}
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	228 \end{funcdesc}
16682 3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	229
19232 65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	230 \begin{funcdesc}{restore}{sequence, which}
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	231 Return one of the two sequences that generated a delta.
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	232
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	233 Given a \var{sequence} produced by \method{Differ.compare()} or
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	234 \function{ndiff()}, extract lines originating from file 1 or 2
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	235 (parameter \var{which}), stripping off line prefixes.
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	236
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	237 Example:
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	238
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	239 \begin{verbatim}
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	240 >>> diff = ndiff('one\ntwo\nthree\n'.splitlines(1),
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	241 ... 'ore\ntree\nemu\n'.splitlines(1))
20038 8a6f2ee6eaba Make difflib.ndiff() and difflib.Differ.compare() generators. This Tim Peters <tim.peters@gmail.com> parents: 19232 diff changeset	242 >>> diff = list(diff) # materialize the generated delta into a list
19232 65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	243 >>> print ''.join(restore(diff, 1)),
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	244 one
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	245 two
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	246 three
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	247 >>> print ''.join(restore(diff, 2)),
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	248 ore
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	249 tree
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	250 emu
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	251 \end{verbatim}
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	252
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	253 \end{funcdesc}
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	254
33754 10b25414628c SF bug 1046690: difflib.HtmlDiff doc errors. Tim Peters <tim.peters@gmail.com> parents: 33462 diff changeset	255 \begin{funcdesc}{unified_diff}{a, b\optional{, fromfile}\optional{,
10b25414628c SF bug 1046690: difflib.HtmlDiff doc errors. Tim Peters <tim.peters@gmail.com> parents: 33462 diff changeset	256 tofile}\optional{, fromfiledate}\optional{, tofiledate}\optional{,
10b25414628c SF bug 1046690: difflib.HtmlDiff doc errors. Tim Peters <tim.peters@gmail.com> parents: 33462 diff changeset	257 n}\optional{, lineterm}}
29398 e6b0a406dc31 Document context_diff() and unified_diff() Raymond Hettinger <python@rcn.com> parents: 26556 diff changeset	258 Compare \var{a} and \var{b} (lists of strings); return a
e6b0a406dc31 Document context_diff() and unified_diff() Raymond Hettinger <python@rcn.com> parents: 26556 diff changeset	259 delta (a generator generating the delta lines) in unified diff
e6b0a406dc31 Document context_diff() and unified_diff() Raymond Hettinger <python@rcn.com> parents: 26556 diff changeset	260 format.
33462 5876636ca8c6 HtmlDiff corrections from Dan Gass, + trimmed trailing whitespace. Tim Peters <tim.peters@gmail.com> parents: 33448 diff changeset	261
29398 e6b0a406dc31 Document context_diff() and unified_diff() Raymond Hettinger <python@rcn.com> parents: 26556 diff changeset	262 Unified diffs are a compact way of showing just the lines that have
e6b0a406dc31 Document context_diff() and unified_diff() Raymond Hettinger <python@rcn.com> parents: 26556 diff changeset	263 changed plus a few lines of context. The changes are shown in a
e6b0a406dc31 Document context_diff() and unified_diff() Raymond Hettinger <python@rcn.com> parents: 26556 diff changeset	264 inline style (instead of separate before/after blocks). The number
e6b0a406dc31 Document context_diff() and unified_diff() Raymond Hettinger <python@rcn.com> parents: 26556 diff changeset	265 of context lines is set by \var{n} which defaults to three.
e6b0a406dc31 Document context_diff() and unified_diff() Raymond Hettinger <python@rcn.com> parents: 26556 diff changeset	266
e6b0a406dc31 Document context_diff() and unified_diff() Raymond Hettinger <python@rcn.com> parents: 26556 diff changeset	267 By default, the diff control lines (those with \code{---}, \code{+++},
e6b0a406dc31 Document context_diff() and unified_diff() Raymond Hettinger <python@rcn.com> parents: 26556 diff changeset	268 or \code{@@}) are created with a trailing newline. This is helpful so
e6b0a406dc31 Document context_diff() and unified_diff() Raymond Hettinger <python@rcn.com> parents: 26556 diff changeset	269 that inputs created from \function{file.readlines()} result in diffs
e6b0a406dc31 Document context_diff() and unified_diff() Raymond Hettinger <python@rcn.com> parents: 26556 diff changeset	270 that are suitable for use with \function{file.writelines()} since both
e6b0a406dc31 Document context_diff() and unified_diff() Raymond Hettinger <python@rcn.com> parents: 26556 diff changeset	271 the inputs and outputs have trailing newlines.
e6b0a406dc31 Document context_diff() and unified_diff() Raymond Hettinger <python@rcn.com> parents: 26556 diff changeset	272
e6b0a406dc31 Document context_diff() and unified_diff() Raymond Hettinger <python@rcn.com> parents: 26556 diff changeset	273 For inputs that do not have trailing newlines, set the \var{lineterm}
e6b0a406dc31 Document context_diff() and unified_diff() Raymond Hettinger <python@rcn.com> parents: 26556 diff changeset	274 argument to \code{""} so that the output will be uniformly newline free.
e6b0a406dc31 Document context_diff() and unified_diff() Raymond Hettinger <python@rcn.com> parents: 26556 diff changeset	275
e6b0a406dc31 Document context_diff() and unified_diff() Raymond Hettinger <python@rcn.com> parents: 26556 diff changeset	276 The context diff format normally has a header for filenames and
e6b0a406dc31 Document context_diff() and unified_diff() Raymond Hettinger <python@rcn.com> parents: 26556 diff changeset	277 modification times. Any or all of these may be specified using strings for
e6b0a406dc31 Document context_diff() and unified_diff() Raymond Hettinger <python@rcn.com> parents: 26556 diff changeset	278 \var{fromfile}, \var{tofile}, \var{fromfiledate}, and \var{tofiledate}.
e6b0a406dc31 Document context_diff() and unified_diff() Raymond Hettinger <python@rcn.com> parents: 26556 diff changeset	279 The modification times are normally expressed in the format returned by
e6b0a406dc31 Document context_diff() and unified_diff() Raymond Hettinger <python@rcn.com> parents: 26556 diff changeset	280 \function{time.ctime()}. If not specified, the strings default to blanks.
e6b0a406dc31 Document context_diff() and unified_diff() Raymond Hettinger <python@rcn.com> parents: 26556 diff changeset	281
e6b0a406dc31 Document context_diff() and unified_diff() Raymond Hettinger <python@rcn.com> parents: 26556 diff changeset	282 \file{Tools/scripts/diff.py} is a command-line front-end for this
29404 8c5a6853a02a Add docs for get_grouped_opcodes(). Raymond Hettinger <python@rcn.com> parents: 29398 diff changeset	283 function.
8c5a6853a02a Add docs for get_grouped_opcodes(). Raymond Hettinger <python@rcn.com> parents: 29398 diff changeset	284
33462 5876636ca8c6 HtmlDiff corrections from Dan Gass, + trimmed trailing whitespace. Tim Peters <tim.peters@gmail.com> parents: 33448 diff changeset	285 \versionadded{2.3}
5876636ca8c6 HtmlDiff corrections from Dan Gass, + trimmed trailing whitespace. Tim Peters <tim.peters@gmail.com> parents: 33448 diff changeset	286 \end{funcdesc}
19232 65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	287
20677 f614825d326a Enforce a bit of markup consistency. Fred Drake <fdrake@acm.org> parents: 20038 diff changeset	288 \begin{funcdesc}{IS_LINE_JUNK}{line}
f614825d326a Enforce a bit of markup consistency. Fred Drake <fdrake@acm.org> parents: 20038 diff changeset	289 Return true for ignorable lines. The line \var{line} is ignorable
f614825d326a Enforce a bit of markup consistency. Fred Drake <fdrake@acm.org> parents: 20038 diff changeset	290 if \var{line} is blank or contains a single \character{\#},
f614825d326a Enforce a bit of markup consistency. Fred Drake <fdrake@acm.org> parents: 20038 diff changeset	291 otherwise it is not ignorable. Used as a default for parameter
23300 b5f6e9f6e7f4 Mostly in SequenceMatcher.{__chain_b, find_longest_match}: Tim Peters <tim.peters@gmail.com> parents: 21106 diff changeset	292 \var{linejunk} in \function{ndiff()} before Python 2.3.
19232 65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	293 \end{funcdesc}
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	294
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	295
20677 f614825d326a Enforce a bit of markup consistency. Fred Drake <fdrake@acm.org> parents: 20038 diff changeset	296 \begin{funcdesc}{IS_CHARACTER_JUNK}{ch}
f614825d326a Enforce a bit of markup consistency. Fred Drake <fdrake@acm.org> parents: 20038 diff changeset	297 Return true for ignorable characters. The character \var{ch} is
f614825d326a Enforce a bit of markup consistency. Fred Drake <fdrake@acm.org> parents: 20038 diff changeset	298 ignorable if \var{ch} is a space or tab, otherwise it is not
f614825d326a Enforce a bit of markup consistency. Fred Drake <fdrake@acm.org> parents: 20038 diff changeset	299 ignorable. Used as a default for parameter \var{charjunk} in
19232 65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	300 \function{ndiff()}.
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	301 \end{funcdesc}
16682 3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	302
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	303
17382 d368552c2b72 Add reference to the DDJ article discussing a similar algorithm. Fred Drake <fdrake@acm.org> parents: 16758 diff changeset	304 \begin{seealso}
31410 6e3758ed1ef4 add direct link to the article in DDJ Fred Drake <fdrake@acm.org> parents: 31275 diff changeset	305 \seetitle[http://www.ddj.com/documents/s=1103/ddj8807c/]
6e3758ed1ef4 add direct link to the article in DDJ Fred Drake <fdrake@acm.org> parents: 31275 diff changeset	306 {Pattern Matching: The Gestalt Approach}{Discussion of a
17382 d368552c2b72 Add reference to the DDJ article discussing a similar algorithm. Fred Drake <fdrake@acm.org> parents: 16758 diff changeset	307 similar algorithm by John W. Ratcliff and D. E. Metzener.
d368552c2b72 Add reference to the DDJ article discussing a similar algorithm. Fred Drake <fdrake@acm.org> parents: 16758 diff changeset	308 This was published in
d368552c2b72 Add reference to the DDJ article discussing a similar algorithm. Fred Drake <fdrake@acm.org> parents: 16758 diff changeset	309 \citetitle[http://www.ddj.com/]{Dr. Dobb's Journal} in
d368552c2b72 Add reference to the DDJ article discussing a similar algorithm. Fred Drake <fdrake@acm.org> parents: 16758 diff changeset	310 July, 1988.}
d368552c2b72 Add reference to the DDJ article discussing a similar algorithm. Fred Drake <fdrake@acm.org> parents: 16758 diff changeset	311 \end{seealso}
d368552c2b72 Add reference to the DDJ article discussing a similar algorithm. Fred Drake <fdrake@acm.org> parents: 16758 diff changeset	312
d368552c2b72 Add reference to the DDJ article discussing a similar algorithm. Fred Drake <fdrake@acm.org> parents: 16758 diff changeset	313
16682 3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	314 \subsection{SequenceMatcher Objects \label{sequence-matcher}}
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	315
17780 a1575dbf7d81 Replace "\begin{classdesc}{SomeClass}{\unspecified}" with Fred Drake <fdrake@acm.org> parents: 17388 diff changeset	316 The \class{SequenceMatcher} class has this constructor:
a1575dbf7d81 Replace "\begin{classdesc}{SomeClass}{\unspecified}" with Fred Drake <fdrake@acm.org> parents: 17388 diff changeset	317
16682 3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	318 \begin{classdesc}{SequenceMatcher}{\optional{isjunk\optional{,
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	319 a\optional{, b}}}}
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	320 Optional argument \var{isjunk} must be \code{None} (the default) or
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	321 a one-argument function that takes a sequence element and returns
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	322 true if and only if the element is ``junk'' and should be ignored.
33909 2fa872784eb6 SF bug #1060825: Error in difflib docs Raymond Hettinger <python@rcn.com> parents: 33754 diff changeset	323 Passing \code{None} for \var{isjunk} is equivalent to passing
20677 f614825d326a Enforce a bit of markup consistency. Fred Drake <fdrake@acm.org> parents: 20038 diff changeset	324 \code{lambda x: 0}; in other words, no elements are ignored. For
f614825d326a Enforce a bit of markup consistency. Fred Drake <fdrake@acm.org> parents: 20038 diff changeset	325 example, pass:
16682 3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	326
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	327 \begin{verbatim}
16758 8996288a8873 Fix extra backslash in example. Fred Drake <fdrake@acm.org> parents: 16703 diff changeset	328 lambda x: x in " \t"
16682 3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	329 \end{verbatim}
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	330
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	331 if you're comparing lines as sequences of characters, and don't want
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	332 to synch up on blanks or hard tabs.
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	333
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	334 The optional arguments \var{a} and \var{b} are sequences to be
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	335 compared; both default to empty strings. The elements of both
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	336 sequences must be hashable.
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	337 \end{classdesc}
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	338
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	339
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	340 \class{SequenceMatcher} objects have the following methods:
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	341
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	342 \begin{methoddesc}{set_seqs}{a, b}
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	343 Set the two sequences to be compared.
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	344 \end{methoddesc}
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	345
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	346 \class{SequenceMatcher} computes and caches detailed information about
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	347 the second sequence, so if you want to compare one sequence against
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	348 many sequences, use \method{set_seq2()} to set the commonly used
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	349 sequence once and call \method{set_seq1()} repeatedly, once for each
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	350 of the other sequences.
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	351
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	352 \begin{methoddesc}{set_seq1}{a}
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	353 Set the first sequence to be compared. The second sequence to be
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	354 compared is not changed.
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	355 \end{methoddesc}
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	356
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	357 \begin{methoddesc}{set_seq2}{b}
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	358 Set the second sequence to be compared. The first sequence to be
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	359 compared is not changed.
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	360 \end{methoddesc}
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	361
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	362 \begin{methoddesc}{find_longest_match}{alo, ahi, blo, bhi}
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	363 Find longest matching block in \code{\var{a}[\var{alo}:\var{ahi}]}
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	364 and \code{\var{b}[\var{blo}:\var{bhi}]}.
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	365
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	366 If \var{isjunk} was omitted or \code{None},
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	367 \method{get_longest_match()} returns \code{(\var{i}, \var{j},
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	368 \var{k})} such that \code{\var{a}[\var{i}:\var{i}+\var{k}]} is equal
20038 8a6f2ee6eaba Make difflib.ndiff() and difflib.Differ.compare() generators. This Tim Peters <tim.peters@gmail.com> parents: 19232 diff changeset	369 to \code{\var{b}[\var{j}:\var{j}+\var{k}]}, where
16682 3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	370 \code{\var{alo} <= \var{i} <= \var{i}+\var{k} <= \var{ahi}} and
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	371 \code{\var{blo} <= \var{j} <= \var{j}+\var{k} <= \var{bhi}}.
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	372 For all \code{(\var{i'}, \var{j'}, \var{k'})} meeting those
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	373 conditions, the additional conditions
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	374 \code{\var{k} >= \var{k'}},
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	375 \code{\var{i} <= \var{i'}},
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	376 and if \code{\var{i} == \var{i'}}, \code{\var{j} <= \var{j'}}
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	377 are also met.
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	378 In other words, of all maximal matching blocks, return one that
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	379 starts earliest in \var{a}, and of all those maximal matching blocks
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	380 that start earliest in \var{a}, return the one that starts earliest
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	381 in \var{b}.
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	382
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	383 \begin{verbatim}
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	384 >>> s = SequenceMatcher(None, " abcd", "abcd abcd")
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	385 >>> s.find_longest_match(0, 5, 0, 9)
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	386 (0, 4, 5)
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	387 \end{verbatim}
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	388
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	389 If \var{isjunk} was provided, first the longest matching block is
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	390 determined as above, but with the additional restriction that no
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	391 junk element appears in the block. Then that block is extended as
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	392 far as possible by matching (only) junk elements on both sides.
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	393 So the resulting block never matches on junk except as identical
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	394 junk happens to be adjacent to an interesting match.
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	395
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	396 Here's the same example as before, but considering blanks to be junk.
16703 8172906c6dc8 Improve accuracy. In the .tex file, note the new "% BUG:" comments: an Tim Peters <tim.peters@gmail.com> parents: 16682 diff changeset	397 That prevents \code{' abcd'} from matching the \code{' abcd'} at the
16682 3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	398 tail end of the second sequence directly. Instead only the
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	399 \code{'abcd'} can match, and matches the leftmost \code{'abcd'} in
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	400 the second sequence:
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	401
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	402 \begin{verbatim}
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	403 >>> s = SequenceMatcher(lambda x: x==" ", " abcd", "abcd abcd")
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	404 >>> s.find_longest_match(0, 5, 0, 9)
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	405 (1, 0, 4)
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	406 \end{verbatim}
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	407
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	408 If no blocks match, this returns \code{(\var{alo}, \var{blo}, 0)}.
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	409 \end{methoddesc}
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	410
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	411 \begin{methoddesc}{get_matching_blocks}{}
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	412 Return list of triples describing matching subsequences.
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	413 Each triple is of the form \code{(\var{i}, \var{j}, \var{n})}, and
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	414 means that \code{\var{a}[\var{i}:\var{i}+\var{n}] ==
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	415 \var{b}[\var{j}:\var{j}+\var{n}]}. The triples are monotonically
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	416 increasing in \var{i} and \var{j}.
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	417
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	418 The last triple is a dummy, and has the value \code{(len(\var{a}),
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	419 len(\var{b}), 0)}. It is the only triple with \code{\var{n} == 0}.
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	420 % Explain why a dummy is used!
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	421
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	422 \begin{verbatim}
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	423 >>> s = SequenceMatcher(None, "abxcd", "abcd")
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	424 >>> s.get_matching_blocks()
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	425 [(0, 0, 2), (3, 2, 2), (5, 4, 0)]
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	426 \end{verbatim}
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	427 \end{methoddesc}
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	428
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	429 \begin{methoddesc}{get_opcodes}{}
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	430 Return list of 5-tuples describing how to turn \var{a} into \var{b}.
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	431 Each tuple is of the form \code{(\var{tag}, \var{i1}, \var{i2},
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	432 \var{j1}, \var{j2})}. The first tuple has \code{\var{i1} ==
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	433 \var{j1} == 0}, and remaining tuples have \var{i1} equal to the
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	434 \var{i2} from the preceeding tuple, and, likewise, \var{j1} equal to
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	435 the previous \var{j2}.
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	436
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	437 The \var{tag} values are strings, with these meanings:
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	438
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	439 \begin{tableii}{l\|l}{code}{Value}{Meaning}
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	440 \lineii{'replace'}{\code{\var{a}[\var{i1}:\var{i2}]} should be
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	441 replaced by \code{\var{b}[\var{j1}:\var{j2}]}.}
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	442 \lineii{'delete'}{\code{\var{a}[\var{i1}:\var{i2}]} should be
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	443 deleted. Note that \code{\var{j1} == \var{j2}} in
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	444 this case.}
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	445 \lineii{'insert'}{\code{\var{b}[\var{j1}:\var{j2}]} should be
20038 8a6f2ee6eaba Make difflib.ndiff() and difflib.Differ.compare() generators. This Tim Peters <tim.peters@gmail.com> parents: 19232 diff changeset	446 inserted at \code{\var{a}[\var{i1}:\var{i1}]}.
16682 3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	447 Note that \code{\var{i1} == \var{i2}} in this
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	448 case.}
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	449 \lineii{'equal'}{\code{\var{a}[\var{i1}:\var{i2}] ==
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	450 \var{b}[\var{j1}:\var{j2}]} (the sub-sequences are
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	451 equal).}
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	452 \end{tableii}
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	453
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	454 For example:
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	455
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	456 \begin{verbatim}
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	457 >>> a = "qabxcd"
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	458 >>> b = "abycdf"
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	459 >>> s = SequenceMatcher(None, a, b)
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	460 >>> for tag, i1, i2, j1, j2 in s.get_opcodes():
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	461 ... print ("%7s a[%d:%d] (%s) b[%d:%d] (%s)" %
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	462 ... (tag, i1, i2, a[i1:i2], j1, j2, b[j1:j2]))
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	463 delete a[0:1] (q) b[0:0] ()
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	464 equal a[1:3] (ab) b[0:2] (ab)
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	465 replace a[3:4] (x) b[2:3] (y)
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	466 equal a[4:6] (cd) b[3:5] (cd)
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	467 insert a[6:6] () b[5:6] (f)
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	468 \end{verbatim}
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	469 \end{methoddesc}
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	470
29404 8c5a6853a02a Add docs for get_grouped_opcodes(). Raymond Hettinger <python@rcn.com> parents: 29398 diff changeset	471 \begin{methoddesc}{get_grouped_opcodes}{\optional{n}}
8c5a6853a02a Add docs for get_grouped_opcodes(). Raymond Hettinger <python@rcn.com> parents: 29398 diff changeset	472 Return a generator of groups with up to \var{n} lines of context.
8c5a6853a02a Add docs for get_grouped_opcodes(). Raymond Hettinger <python@rcn.com> parents: 29398 diff changeset	473
8c5a6853a02a Add docs for get_grouped_opcodes(). Raymond Hettinger <python@rcn.com> parents: 29398 diff changeset	474 Starting with the groups returned by \method{get_opcodes()},
8c5a6853a02a Add docs for get_grouped_opcodes(). Raymond Hettinger <python@rcn.com> parents: 29398 diff changeset	475 this method splits out smaller change clusters and eliminates
8c5a6853a02a Add docs for get_grouped_opcodes(). Raymond Hettinger <python@rcn.com> parents: 29398 diff changeset	476 intervening ranges which have no changes.
8c5a6853a02a Add docs for get_grouped_opcodes(). Raymond Hettinger <python@rcn.com> parents: 29398 diff changeset	477
8c5a6853a02a Add docs for get_grouped_opcodes(). Raymond Hettinger <python@rcn.com> parents: 29398 diff changeset	478 The groups are returned in the same format as \method{get_opcodes()}.
33462 5876636ca8c6 HtmlDiff corrections from Dan Gass, + trimmed trailing whitespace. Tim Peters <tim.peters@gmail.com> parents: 33448 diff changeset	479 \versionadded{2.3}
29404 8c5a6853a02a Add docs for get_grouped_opcodes(). Raymond Hettinger <python@rcn.com> parents: 29398 diff changeset	480 \end{methoddesc}
8c5a6853a02a Add docs for get_grouped_opcodes(). Raymond Hettinger <python@rcn.com> parents: 29398 diff changeset	481
16682 3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	482 \begin{methoddesc}{ratio}{}
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	483 Return a measure of the sequences' similarity as a float in the
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	484 range [0, 1].
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	485
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	486 Where T is the total number of elements in both sequences, and M is
19232 65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	487 the number of matches, this is 2.0*M / T. Note that this is
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	488 \code{1.0} if the sequences are identical, and \code{0.0} if they
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	489 have nothing in common.
16682 3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	490
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	491 This is expensive to compute if \method{get_matching_blocks()} or
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	492 \method{get_opcodes()} hasn't already been called, in which case you
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	493 may want to try \method{quick_ratio()} or
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	494 \method{real_quick_ratio()} first to get an upper bound.
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	495 \end{methoddesc}
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	496
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	497 \begin{methoddesc}{quick_ratio}{}
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	498 Return an upper bound on \method{ratio()} relatively quickly.
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	499
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	500 This isn't defined beyond that it is an upper bound on
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	501 \method{ratio()}, and is faster to compute.
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	502 \end{methoddesc}
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	503
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	504 \begin{methoddesc}{real_quick_ratio}{}
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	505 Return an upper bound on \method{ratio()} very quickly.
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	506
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	507 This isn't defined beyond that it is an upper bound on
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	508 \method{ratio()}, and is faster to compute than either
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	509 \method{ratio()} or \method{quick_ratio()}.
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	510 \end{methoddesc}
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	511
16703 8172906c6dc8 Improve accuracy. In the .tex file, note the new "% BUG:" comments: an Tim Peters <tim.peters@gmail.com> parents: 16682 diff changeset	512 The three methods that return the ratio of matching to total characters
8172906c6dc8 Improve accuracy. In the .tex file, note the new "% BUG:" comments: an Tim Peters <tim.peters@gmail.com> parents: 16682 diff changeset	513 can give different results due to differing levels of approximation,
8172906c6dc8 Improve accuracy. In the .tex file, note the new "% BUG:" comments: an Tim Peters <tim.peters@gmail.com> parents: 16682 diff changeset	514 although \method{quick_ratio()} and \method{real_quick_ratio()} are always
8172906c6dc8 Improve accuracy. In the .tex file, note the new "% BUG:" comments: an Tim Peters <tim.peters@gmail.com> parents: 16682 diff changeset	515 at least as large as \method{ratio()}:
16682 3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	516
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	517 \begin{verbatim}
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	518 >>> s = SequenceMatcher(None, "abcd", "bcde")
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	519 >>> s.ratio()
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	520 0.75
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	521 >>> s.quick_ratio()
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	522 0.75
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	523 >>> s.real_quick_ratio()
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	524 1.0
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	525 \end{verbatim}
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	526
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	527
19232 65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	528 \subsection{SequenceMatcher Examples \label{sequencematcher-examples}}
16682 3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	529
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	530
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	531 This example compares two strings, considering blanks to be ``junk:''
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	532
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	533 \begin{verbatim}
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	534 >>> s = SequenceMatcher(lambda x: x == " ",
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	535 ... "private Thread currentThread;",
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	536 ... "private volatile Thread currentThread;")
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	537 \end{verbatim}
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	538
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	539 \method{ratio()} returns a float in [0, 1], measuring the similarity
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	540 of the sequences. As a rule of thumb, a \method{ratio()} value over
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	541 0.6 means the sequences are close matches:
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	542
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	543 \begin{verbatim}
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	544 >>> print round(s.ratio(), 3)
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	545 0.866
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	546 \end{verbatim}
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	547
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	548 If you're only interested in where the sequences match,
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	549 \method{get_matching_blocks()} is handy:
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	550
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	551 \begin{verbatim}
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	552 >>> for block in s.get_matching_blocks():
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	553 ... print "a[%d] and b[%d] match for %d elements" % block
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	554 a[0] and b[0] match for 8 elements
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	555 a[8] and b[17] match for 6 elements
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	556 a[14] and b[23] match for 15 elements
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	557 a[29] and b[38] match for 0 elements
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	558 \end{verbatim}
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	559
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	560 Note that the last tuple returned by \method{get_matching_blocks()} is
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	561 always a dummy, \code{(len(\var{a}), len(\var{b}), 0)}, and this is
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	562 the only case in which the last tuple element (number of elements
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	563 matched) is \code{0}.
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	564
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	565 If you want to know how to change the first sequence into the second,
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	566 use \method{get_opcodes()}:
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	567
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	568 \begin{verbatim}
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	569 >>> for opcode in s.get_opcodes():
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	570 ... print "%6s a[%d:%d] b[%d:%d]" % opcode
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	571 equal a[0:8] b[0:8]
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	572 insert a[8:8] b[8:17]
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	573 equal a[8:14] b[17:23]
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	574 equal a[14:29] b[23:38]
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	575 \end{verbatim}
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	576
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	577 See also the function \function{get_close_matches()} in this module,
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	578 which shows how simple code building on \class{SequenceMatcher} can be
3cb00cbe7455 Documentation for the difflib module, converted from the module docstrings. Fred Drake <fdrake@acm.org> parents: diff changeset	579 used to do useful work.
19232 65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	580
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	581
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	582 \subsection{Differ Objects \label{differ-objects}}
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	583
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	584 Note that \class{Differ}-generated deltas make no claim to be
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	585 \strong{minimal} diffs. To the contrary, minimal diffs are often
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	586 counter-intuitive, because they synch up anywhere possible, sometimes
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	587 accidental matches 100 pages apart. Restricting synch points to
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	588 contiguous matches preserves some notion of locality, at the
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	589 occasional cost of producing a longer diff.
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	590
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	591 The \class{Differ} class has this constructor:
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	592
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	593 \begin{classdesc}{Differ}{\optional{linejunk\optional{, charjunk}}}
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	594 Optional keyword parameters \var{linejunk} and \var{charjunk} are
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	595 for filter functions (or \code{None}):
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	596
23300 b5f6e9f6e7f4 Mostly in SequenceMatcher.{__chain_b, find_longest_match}: Tim Peters <tim.peters@gmail.com> parents: 21106 diff changeset	597 \var{linejunk}: A function that accepts a single string
b5f6e9f6e7f4 Mostly in SequenceMatcher.{__chain_b, find_longest_match}: Tim Peters <tim.peters@gmail.com> parents: 21106 diff changeset	598 argument, and returns true if the string is junk. The default is
b5f6e9f6e7f4 Mostly in SequenceMatcher.{__chain_b, find_longest_match}: Tim Peters <tim.peters@gmail.com> parents: 21106 diff changeset	599 \code{None}, meaning that no line is considered junk.
19232 65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	600
23300 b5f6e9f6e7f4 Mostly in SequenceMatcher.{__chain_b, find_longest_match}: Tim Peters <tim.peters@gmail.com> parents: 21106 diff changeset	601 \var{charjunk}: A function that accepts a single character argument
b5f6e9f6e7f4 Mostly in SequenceMatcher.{__chain_b, find_longest_match}: Tim Peters <tim.peters@gmail.com> parents: 21106 diff changeset	602 (a string of length 1), and returns true if the character is junk.
b5f6e9f6e7f4 Mostly in SequenceMatcher.{__chain_b, find_longest_match}: Tim Peters <tim.peters@gmail.com> parents: 21106 diff changeset	603 The default is \code{None}, meaning that no character is
b5f6e9f6e7f4 Mostly in SequenceMatcher.{__chain_b, find_longest_match}: Tim Peters <tim.peters@gmail.com> parents: 21106 diff changeset	604 considered junk.
19232 65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	605 \end{classdesc}
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	606
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	607 \class{Differ} objects are used (deltas generated) via a single
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	608 method:
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	609
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	610 \begin{methoddesc}{compare}{a, b}
20038 8a6f2ee6eaba Make difflib.ndiff() and difflib.Differ.compare() generators. This Tim Peters <tim.peters@gmail.com> parents: 19232 diff changeset	611 Compare two sequences of lines, and generate the delta (a sequence
8a6f2ee6eaba Make difflib.ndiff() and difflib.Differ.compare() generators. This Tim Peters <tim.peters@gmail.com> parents: 19232 diff changeset	612 of lines).
19232 65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	613
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	614 Each sequence must contain individual single-line strings ending
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	615 with newlines. Such sequences can be obtained from the
20038 8a6f2ee6eaba Make difflib.ndiff() and difflib.Differ.compare() generators. This Tim Peters <tim.peters@gmail.com> parents: 19232 diff changeset	616 \method{readlines()} method of file-like objects. The delta generated
8a6f2ee6eaba Make difflib.ndiff() and difflib.Differ.compare() generators. This Tim Peters <tim.peters@gmail.com> parents: 19232 diff changeset	617 also consists of newline-terminated strings, ready to be printed as-is
21106 3827f136e0d6 writeline() --> writelines() Fred Drake <fdrake@acm.org> parents: 20677 diff changeset	618 via the \method{writelines()} method of a file-like object.
19232 65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	619 \end{methoddesc}
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	620
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	621
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	622 \subsection{Differ Example \label{differ-examples}}
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	623
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	624 This example compares two texts. First we set up the texts, sequences
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	625 of individual single-line strings ending with newlines (such sequences
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	626 can also be obtained from the \method{readlines()} method of file-like
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	627 objects):
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	628
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	629 \begin{verbatim}
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	630 >>> text1 = ''' 1. Beautiful is better than ugly.
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	631 ... 2. Explicit is better than implicit.
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	632 ... 3. Simple is better than complex.
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	633 ... 4. Complex is better than complicated.
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	634 ... '''.splitlines(1)
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	635 >>> len(text1)
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	636 4
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	637 >>> text1[0][-1]
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	638 '\n'
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	639 >>> text2 = ''' 1. Beautiful is better than ugly.
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	640 ... 3. Simple is better than complex.
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	641 ... 4. Complicated is better than complex.
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	642 ... 5. Flat is better than nested.
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	643 ... '''.splitlines(1)
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	644 \end{verbatim}
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	645
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	646 Next we instantiate a Differ object:
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	647
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	648 \begin{verbatim}
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	649 >>> d = Differ()
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	650 \end{verbatim}
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	651
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	652 Note that when instantiating a \class{Differ} object we may pass
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	653 functions to filter out line and character ``junk.'' See the
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	654 \method{Differ()} constructor for details.
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	655
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	656 Finally, we compare the two:
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	657
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	658 \begin{verbatim}
20038 8a6f2ee6eaba Make difflib.ndiff() and difflib.Differ.compare() generators. This Tim Peters <tim.peters@gmail.com> parents: 19232 diff changeset	659 >>> result = list(d.compare(text1, text2))
19232 65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	660 \end{verbatim}
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	661
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	662 \code{result} is a list of strings, so let's pretty-print it:
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	663
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	664 \begin{verbatim}
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	665 >>> from pprint import pprint
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	666 >>> pprint(result)
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	667 [' 1. Beautiful is better than ugly.\n',
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	668 '- 2. Explicit is better than implicit.\n',
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	669 '- 3. Simple is better than complex.\n',
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	670 '+ 3. Simple is better than complex.\n',
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	671 '? ++ \n',
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	672 '- 4. Complex is better than complicated.\n',
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	673 '? ^ ---- ^ \n',
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	674 '+ 4. Complicated is better than complex.\n',
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	675 '? ++++ ^ ^ \n',
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	676 '+ 5. Flat is better than nested.\n']
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	677 \end{verbatim}
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	678
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	679 As a single multi-line string it looks like this:
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	680
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	681 \begin{verbatim}
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	682 >>> import sys
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	683 >>> sys.stdout.writelines(result)
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	684 1. Beautiful is better than ugly.
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	685 - 2. Explicit is better than implicit.
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	686 - 3. Simple is better than complex.
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	687 + 3. Simple is better than complex.
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	688 ? ++
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	689 - 4. Complex is better than complicated.
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	690 ? ^ ---- ^
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	691 + 4. Complicated is better than complex.
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	692 ? ++++ ^ ^
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	693 + 5. Flat is better than nested.
65885ea76c37 David Goodger <dgoodger@atsautomation.com>: Fred Drake <fdrake@acm.org> parents: 17785 diff changeset	694 \end{verbatim}

Mercurial > cpython-lru_cache-weakref

annotate Doc/lib/libdifflib.tex @ 33909:2fa872784eb6 legacy-trunk