Mercurial > cpython-lru_cache-weakref

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Add use_weakref option to functools.lru_cache The use_weakref option makes lru_cache create weak references to the function arguments when creating the cache key, which prevents them from staying in the memory forever even after all other references to them are gone. This is a proof of concept for http://bugs.python.org/issue19859
author Radomir Dopieralski <devel@sheep.art.pl>
date Tue, 03 Dec 2013 16:02:48 +0100
parents 68cbf6551710
children
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1 .. highlightlang:: c
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2
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3 .. _floatobjects:
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4
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5 Floating Point Objects
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6 ----------------------
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7
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8 .. index:: object: floating point
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11 .. c:type:: PyFloatObject
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13 This subtype of :c:type:`PyObject` represents a Python floating point object.
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16 .. c:var:: PyTypeObject PyFloat_Type
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18 This instance of :c:type:`PyTypeObject` represents the Python floating point
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19 type. This is the same object as :class:`float` in the Python layer.
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22 .. c:function:: int PyFloat_Check(PyObject *p)
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24 Return true if its argument is a :c:type:`PyFloatObject` or a subtype of
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25 :c:type:`PyFloatObject`.
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28 .. c:function:: int PyFloat_CheckExact(PyObject *p)
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30 Return true if its argument is a :c:type:`PyFloatObject`, but not a subtype of
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31 :c:type:`PyFloatObject`.
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34 .. c:function:: PyObject* PyFloat_FromString(PyObject *str)
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36 Create a :c:type:`PyFloatObject` object based on the string value in *str*, or
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37 *NULL* on failure.
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40 .. c:function:: PyObject* PyFloat_FromDouble(double v)
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42 Create a :c:type:`PyFloatObject` object from *v*, or *NULL* on failure.
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45 .. c:function:: double PyFloat_AsDouble(PyObject *pyfloat)
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47 Return a C :c:type:`double` representation of the contents of *pyfloat*. If
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48 *pyfloat* is not a Python floating point object but has a :meth:`__float__`
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49 method, this method will first be called to convert *pyfloat* into a float.
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50 This method returns ``-1.0`` upon failure, so one should call
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51 :c:func:`PyErr_Occurred` to check for errors.
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54 .. c:function:: double PyFloat_AS_DOUBLE(PyObject *pyfloat)
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56 Return a C :c:type:`double` representation of the contents of *pyfloat*, but
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57 without error checking.
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60 .. c:function:: PyObject* PyFloat_GetInfo(void)
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62 Return a structseq instance which contains information about the
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63 precision, minimum and maximum values of a float. It's a thin wrapper
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64 around the header file :file:`float.h`.
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67 .. c:function:: double PyFloat_GetMax()
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69 Return the maximum representable finite float *DBL_MAX* as C :c:type:`double`.
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72 .. c:function:: double PyFloat_GetMin()
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74 Return the minimum normalized positive float *DBL_MIN* as C :c:type:`double`.
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76 .. c:function:: int PyFloat_ClearFreeList()
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78 Clear the float free list. Return the number of items that could not
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79 be freed.