author | martin.trojer@nokia.com |
Fri, 31 Jul 2009 15:01:17 +0100 | |
changeset 1 | 2fb8b9db1c86 |
permissions | -rw-r--r-- |
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What's New in Python 2.1 |
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**************************** |
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:Author: A.M. Kuchling |
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.. |release| replace:: 1.01 |
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.. $Id: whatsnew21.tex 50964 2006-07-30 03:03:43Z fred.drake $ |
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Introduction |
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============ |
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This article explains the new features in Python 2.1. While there aren't as |
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many changes in 2.1 as there were in Python 2.0, there are still some pleasant |
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surprises in store. 2.1 is the first release to be steered through the use of |
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Python Enhancement Proposals, or PEPs, so most of the sizable changes have |
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accompanying PEPs that provide more complete documentation and a design |
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rationale for the change. This article doesn't attempt to document the new |
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features completely, but simply provides an overview of the new features for |
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Python programmers. Refer to the Python 2.1 documentation, or to the specific |
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PEP, for more details about any new feature that particularly interests you. |
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One recent goal of the Python development team has been to accelerate the pace |
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of new releases, with a new release coming every 6 to 9 months. 2.1 is the first |
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release to come out at this faster pace, with the first alpha appearing in |
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January, 3 months after the final version of 2.0 was released. |
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The final release of Python 2.1 was made on April 17, 2001. |
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.. ====================================================================== |
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PEP 227: Nested Scopes |
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====================== |
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The largest change in Python 2.1 is to Python's scoping rules. In Python 2.0, |
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at any given time there are at most three namespaces used to look up variable |
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names: local, module-level, and the built-in namespace. This often surprised |
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people because it didn't match their intuitive expectations. For example, a |
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nested recursive function definition doesn't work:: |
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def f(): |
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... |
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def g(value): |
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... |
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return g(value-1) + 1 |
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... |
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The function :func:`g` will always raise a :exc:`NameError` exception, because |
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the binding of the name ``g`` isn't in either its local namespace or in the |
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module-level namespace. This isn't much of a problem in practice (how often do |
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you recursively define interior functions like this?), but this also made using |
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the :keyword:`lambda` statement clumsier, and this was a problem in practice. |
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In code which uses :keyword:`lambda` you can often find local variables being |
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copied by passing them as the default values of arguments. :: |
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def find(self, name): |
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"Return list of any entries equal to 'name'" |
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L = filter(lambda x, name=name: x == name, |
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self.list_attribute) |
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return L |
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The readability of Python code written in a strongly functional style suffers |
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greatly as a result. |
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The most significant change to Python 2.1 is that static scoping has been added |
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to the language to fix this problem. As a first effect, the ``name=name`` |
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default argument is now unnecessary in the above example. Put simply, when a |
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given variable name is not assigned a value within a function (by an assignment, |
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or the :keyword:`def`, :keyword:`class`, or :keyword:`import` statements), |
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references to the variable will be looked up in the local namespace of the |
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enclosing scope. A more detailed explanation of the rules, and a dissection of |
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the implementation, can be found in the PEP. |
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This change may cause some compatibility problems for code where the same |
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variable name is used both at the module level and as a local variable within a |
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function that contains further function definitions. This seems rather unlikely |
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though, since such code would have been pretty confusing to read in the first |
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place. |
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One side effect of the change is that the ``from module import *`` and |
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:keyword:`exec` statements have been made illegal inside a function scope under |
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certain conditions. The Python reference manual has said all along that ``from |
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module import *`` is only legal at the top level of a module, but the CPython |
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interpreter has never enforced this before. As part of the implementation of |
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nested scopes, the compiler which turns Python source into bytecodes has to |
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generate different code to access variables in a containing scope. ``from |
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module import *`` and :keyword:`exec` make it impossible for the compiler to |
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figure this out, because they add names to the local namespace that are |
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unknowable at compile time. Therefore, if a function contains function |
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definitions or :keyword:`lambda` expressions with free variables, the compiler |
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will flag this by raising a :exc:`SyntaxError` exception. |
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To make the preceding explanation a bit clearer, here's an example:: |
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x = 1 |
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def f(): |
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# The next line is a syntax error |
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exec 'x=2' |
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def g(): |
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return x |
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Line 4 containing the :keyword:`exec` statement is a syntax error, since |
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:keyword:`exec` would define a new local variable named ``x`` whose value should |
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be accessed by :func:`g`. |
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108 |
|
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This shouldn't be much of a limitation, since :keyword:`exec` is rarely used in |
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most Python code (and when it is used, it's often a sign of a poor design |
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anyway). |
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112 |
|
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Compatibility concerns have led to nested scopes being introduced gradually; in |
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Python 2.1, they aren't enabled by default, but can be turned on within a module |
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by using a future statement as described in PEP 236. (See the following section |
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for further discussion of PEP 236.) In Python 2.2, nested scopes will become |
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the default and there will be no way to turn them off, but users will have had |
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all of 2.1's lifetime to fix any breakage resulting from their introduction. |
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119 |
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120 |
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.. seealso:: |
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122 |
|
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:pep:`227` - Statically Nested Scopes |
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Written and implemented by Jeremy Hylton. |
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125 |
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.. ====================================================================== |
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127 |
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128 |
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PEP 236: __future__ Directives |
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============================== |
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131 |
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132 |
The reaction to nested scopes was widespread concern about the dangers of |
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133 |
breaking code with the 2.1 release, and it was strong enough to make the |
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Pythoneers take a more conservative approach. This approach consists of |
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introducing a convention for enabling optional functionality in release N that |
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will become compulsory in release N+1. |
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137 |
|
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138 |
The syntax uses a ``from...import`` statement using the reserved module name |
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:mod:`__future__`. Nested scopes can be enabled by the following statement:: |
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140 |
|
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141 |
from __future__ import nested_scopes |
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142 |
|
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143 |
While it looks like a normal :keyword:`import` statement, it's not; there are |
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strict rules on where such a future statement can be put. They can only be at |
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the top of a module, and must precede any Python code or regular |
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:keyword:`import` statements. This is because such statements can affect how |
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the Python bytecode compiler parses code and generates bytecode, so they must |
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precede any statement that will result in bytecodes being produced. |
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149 |
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150 |
|
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151 |
.. seealso:: |
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152 |
|
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:pep:`236` - Back to the :mod:`__future__` |
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Written by Tim Peters, and primarily implemented by Jeremy Hylton. |
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155 |
|
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.. ====================================================================== |
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157 |
|
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158 |
|
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PEP 207: Rich Comparisons |
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========================= |
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161 |
|
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In earlier versions, Python's support for implementing comparisons on user- |
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defined classes and extension types was quite simple. Classes could implement a |
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:meth:`__cmp__` method that was given two instances of a class, and could only |
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return 0 if they were equal or +1 or -1 if they weren't; the method couldn't |
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raise an exception or return anything other than a Boolean value. Users of |
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Numeric Python often found this model too weak and restrictive, because in the |
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number-crunching programs that numeric Python is used for, it would be more |
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useful to be able to perform elementwise comparisons of two matrices, returning |
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a matrix containing the results of a given comparison for each element. If the |
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two matrices are of different sizes, then the compare has to be able to raise an |
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exception to signal the error. |
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173 |
|
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In Python 2.1, rich comparisons were added in order to support this need. |
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Python classes can now individually overload each of the ``<``, ``<=``, ``>``, |
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``>=``, ``==``, and ``!=`` operations. The new magic method names are: |
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177 |
|
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+-----------+----------------+ |
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| Operation | Method name | |
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+===========+================+ |
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| ``<`` | :meth:`__lt__` | |
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+-----------+----------------+ |
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| ``<=`` | :meth:`__le__` | |
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+-----------+----------------+ |
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| ``>`` | :meth:`__gt__` | |
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+-----------+----------------+ |
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| ``>=`` | :meth:`__ge__` | |
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+-----------+----------------+ |
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| ``==`` | :meth:`__eq__` | |
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+-----------+----------------+ |
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| ``!=`` | :meth:`__ne__` | |
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+-----------+----------------+ |
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193 |
|
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(The magic methods are named after the corresponding Fortran operators ``.LT.``. |
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``.LE.``, &c. Numeric programmers are almost certainly quite familiar with |
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these names and will find them easy to remember.) |
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197 |
|
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Each of these magic methods is of the form ``method(self, other)``, where |
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``self`` will be the object on the left-hand side of the operator, while |
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``other`` will be the object on the right-hand side. For example, the |
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expression ``A < B`` will cause ``A.__lt__(B)`` to be called. |
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202 |
|
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Each of these magic methods can return anything at all: a Boolean, a matrix, a |
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list, or any other Python object. Alternatively they can raise an exception if |
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the comparison is impossible, inconsistent, or otherwise meaningless. |
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206 |
|
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The built-in :func:`cmp(A,B)` function can use the rich comparison machinery, |
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and now accepts an optional argument specifying which comparison operation to |
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use; this is given as one of the strings ``"<"``, ``"<="``, ``">"``, ``">="``, |
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``"=="``, or ``"!="``. If called without the optional third argument, |
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:func:`cmp` will only return -1, 0, or +1 as in previous versions of Python; |
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212 |
otherwise it will call the appropriate method and can return any Python object. |
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There are also corresponding changes of interest to C programmers; there's a new |
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slot ``tp_richcmp`` in type objects and an API for performing a given rich |
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comparison. I won't cover the C API here, but will refer you to PEP 207, or to |
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2.1's C API documentation, for the full list of related functions. |
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.. seealso:: |
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:pep:`207` - Rich Comparisions |
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Written by Guido van Rossum, heavily based on earlier work by David Ascher, and |
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implemented by Guido van Rossum. |
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.. ====================================================================== |
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PEP 230: Warning Framework |
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========================== |
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231 |
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Over its 10 years of existence, Python has accumulated a certain number of |
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obsolete modules and features along the way. It's difficult to know when a |
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feature is safe to remove, since there's no way of knowing how much code uses it |
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--- perhaps no programs depend on the feature, or perhaps many do. To enable |
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removing old features in a more structured way, a warning framework was added. |
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When the Python developers want to get rid of a feature, it will first trigger a |
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warning in the next version of Python. The following Python version can then |
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drop the feature, and users will have had a full release cycle to remove uses of |
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the old feature. |
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241 |
|
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Python 2.1 adds the warning framework to be used in this scheme. It adds a |
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:mod:`warnings` module that provide functions to issue warnings, and to filter |
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out warnings that you don't want to be displayed. Third-party modules can also |
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use this framework to deprecate old features that they no longer wish to |
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support. |
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247 |
|
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For example, in Python 2.1 the :mod:`regex` module is deprecated, so importing |
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it causes a warning to be printed:: |
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250 |
|
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>>> import regex |
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__main__:1: DeprecationWarning: the regex module |
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is deprecated; please use the re module |
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>>> |
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|
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Warnings can be issued by calling the :func:`warnings.warn` function:: |
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257 |
|
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warnings.warn("feature X no longer supported") |
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259 |
|
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The first parameter is the warning message; an additional optional parameters |
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can be used to specify a particular warning category. |
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262 |
|
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Filters can be added to disable certain warnings; a regular expression pattern |
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can be applied to the message or to the module name in order to suppress a |
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warning. For example, you may have a program that uses the :mod:`regex` module |
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and not want to spare the time to convert it to use the :mod:`re` module right |
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now. The warning can be suppressed by calling :: |
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268 |
|
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import warnings |
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warnings.filterwarnings(action = 'ignore', |
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message='.*regex module is deprecated', |
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category=DeprecationWarning, |
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module = '__main__') |
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|
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This adds a filter that will apply only to warnings of the class |
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:class:`DeprecationWarning` triggered in the :mod:`__main__` module, and applies |
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a regular expression to only match the message about the :mod:`regex` module |
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being deprecated, and will cause such warnings to be ignored. Warnings can also |
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be printed only once, printed every time the offending code is executed, or |
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turned into exceptions that will cause the program to stop (unless the |
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exceptions are caught in the usual way, of course). |
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|
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Functions were also added to Python's C API for issuing warnings; refer to PEP |
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230 or to Python's API documentation for the details. |
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285 |
|
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286 |
|
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.. seealso:: |
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288 |
|
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:pep:`5` - Guidelines for Language Evolution |
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Written by Paul Prescod, to specify procedures to be followed when removing old |
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features from Python. The policy described in this PEP hasn't been officially |
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adopted, but the eventual policy probably won't be too different from Prescod's |
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proposal. |
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294 |
|
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:pep:`230` - Warning Framework |
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Written and implemented by Guido van Rossum. |
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297 |
|
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.. ====================================================================== |
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299 |
|
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|
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PEP 229: New Build System |
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========================= |
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303 |
|
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When compiling Python, the user had to go in and edit the :file:`Modules/Setup` |
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file in order to enable various additional modules; the default set is |
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relatively small and limited to modules that compile on most Unix platforms. |
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This means that on Unix platforms with many more features, most notably Linux, |
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Python installations often don't contain all useful modules they could. |
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|
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Python 2.0 added the Distutils, a set of modules for distributing and installing |
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extensions. In Python 2.1, the Distutils are used to compile much of the |
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standard library of extension modules, autodetecting which ones are supported on |
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the current machine. It's hoped that this will make Python installations easier |
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and more featureful. |
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315 |
|
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Instead of having to edit the :file:`Modules/Setup` file in order to enable |
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modules, a :file:`setup.py` script in the top directory of the Python source |
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distribution is run at build time, and attempts to discover which modules can be |
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319 |
enabled by examining the modules and header files on the system. If a module is |
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|
320 |
configured in :file:`Modules/Setup`, the :file:`setup.py` script won't attempt |
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|
321 |
to compile that module and will defer to the :file:`Modules/Setup` file's |
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|
322 |
contents. This provides a way to specific any strange command-line flags or |
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|
323 |
libraries that are required for a specific platform. |
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|
324 |
|
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|
325 |
In another far-reaching change to the build mechanism, Neil Schemenauer |
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|
326 |
restructured things so Python now uses a single makefile that isn't recursive, |
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|
327 |
instead of makefiles in the top directory and in each of the :file:`Python/`, |
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|
328 |
:file:`Parser/`, :file:`Objects/`, and :file:`Modules/` subdirectories. This |
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|
329 |
makes building Python faster and also makes hacking the Makefiles clearer and |
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|
330 |
simpler. |
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|
331 |
|
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|
332 |
|
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|
333 |
.. seealso:: |
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|
334 |
|
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|
335 |
:pep:`229` - Using Distutils to Build Python |
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|
336 |
Written and implemented by A.M. Kuchling. |
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|
337 |
|
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|
338 |
.. ====================================================================== |
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|
339 |
|
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|
340 |
|
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|
341 |
PEP 205: Weak References |
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|
342 |
======================== |
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|
343 |
|
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|
344 |
Weak references, available through the :mod:`weakref` module, are a minor but |
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|
345 |
useful new data type in the Python programmer's toolbox. |
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|
346 |
|
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|
347 |
Storing a reference to an object (say, in a dictionary or a list) has the side |
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|
348 |
effect of keeping that object alive forever. There are a few specific cases |
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|
349 |
where this behaviour is undesirable, object caches being the most common one, |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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|
350 |
and another being circular references in data structures such as trees. |
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|
351 |
|
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|
352 |
For example, consider a memoizing function that caches the results of another |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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|
353 |
function :func:`f(x)` by storing the function's argument and its result in a |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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|
354 |
dictionary:: |
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changeset
|
355 |
|
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|
356 |
_cache = {} |
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|
357 |
def memoize(x): |
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|
358 |
if _cache.has_key(x): |
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|
359 |
return _cache[x] |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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changeset
|
360 |
|
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Initial QEMU (symbian-qemu-0.9.1-12) import
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|
361 |
retval = f(x) |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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|
362 |
|
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Initial QEMU (symbian-qemu-0.9.1-12) import
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|
363 |
# Cache the returned object |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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|
364 |
_cache[x] = retval |
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changeset
|
365 |
|
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Initial QEMU (symbian-qemu-0.9.1-12) import
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|
366 |
return retval |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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changeset
|
367 |
|
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Initial QEMU (symbian-qemu-0.9.1-12) import
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|
368 |
This version works for simple things such as integers, but it has a side effect; |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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changeset
|
369 |
the ``_cache`` dictionary holds a reference to the return values, so they'll |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
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diff
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|
370 |
never be deallocated until the Python process exits and cleans up This isn't |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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changeset
|
371 |
very noticeable for integers, but if :func:`f` returns an object, or a data |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
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diff
changeset
|
372 |
structure that takes up a lot of memory, this can be a problem. |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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changeset
|
373 |
|
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Initial QEMU (symbian-qemu-0.9.1-12) import
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|
374 |
Weak references provide a way to implement a cache that won't keep objects alive |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
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diff
changeset
|
375 |
beyond their time. If an object is only accessible through weak references, the |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
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diff
changeset
|
376 |
object will be deallocated and the weak references will now indicate that the |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
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changeset
|
377 |
object it referred to no longer exists. A weak reference to an object *obj* is |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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|
378 |
created by calling ``wr = weakref.ref(obj)``. The object being referred to is |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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|
379 |
returned by calling the weak reference as if it were a function: ``wr()``. It |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
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changeset
|
380 |
will return the referenced object, or ``None`` if the object no longer exists. |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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changeset
|
381 |
|
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Initial QEMU (symbian-qemu-0.9.1-12) import
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changeset
|
382 |
This makes it possible to write a :func:`memoize` function whose cache doesn't |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
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diff
changeset
|
383 |
keep objects alive, by storing weak references in the cache. :: |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
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parents:
diff
changeset
|
384 |
|
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Initial QEMU (symbian-qemu-0.9.1-12) import
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diff
changeset
|
385 |
_cache = {} |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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parents:
diff
changeset
|
386 |
def memoize(x): |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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parents:
diff
changeset
|
387 |
if _cache.has_key(x): |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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parents:
diff
changeset
|
388 |
obj = _cache[x]() |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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parents:
diff
changeset
|
389 |
# If weak reference object still exists, |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
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diff
changeset
|
390 |
# return it |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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diff
changeset
|
391 |
if obj is not None: return obj |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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changeset
|
392 |
|
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Initial QEMU (symbian-qemu-0.9.1-12) import
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changeset
|
393 |
retval = f(x) |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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changeset
|
394 |
|
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Initial QEMU (symbian-qemu-0.9.1-12) import
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changeset
|
395 |
# Cache a weak reference |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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changeset
|
396 |
_cache[x] = weakref.ref(retval) |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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changeset
|
397 |
|
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Initial QEMU (symbian-qemu-0.9.1-12) import
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changeset
|
398 |
return retval |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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diff
changeset
|
399 |
|
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Initial QEMU (symbian-qemu-0.9.1-12) import
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diff
changeset
|
400 |
The :mod:`weakref` module also allows creating proxy objects which behave like |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
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parents:
diff
changeset
|
401 |
weak references --- an object referenced only by proxy objects is deallocated -- |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
402 |
but instead of requiring an explicit call to retrieve the object, the proxy |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
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parents:
diff
changeset
|
403 |
transparently forwards all operations to the object as long as the object still |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
404 |
exists. If the object is deallocated, attempting to use a proxy will cause a |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
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diff
changeset
|
405 |
:exc:`weakref.ReferenceError` exception to be raised. :: |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
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parents:
diff
changeset
|
406 |
|
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Initial QEMU (symbian-qemu-0.9.1-12) import
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diff
changeset
|
407 |
proxy = weakref.proxy(obj) |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
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parents:
diff
changeset
|
408 |
proxy.attr # Equivalent to obj.attr |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
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parents:
diff
changeset
|
409 |
proxy.meth() # Equivalent to obj.meth() |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
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diff
changeset
|
410 |
del obj |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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parents:
diff
changeset
|
411 |
proxy.attr # raises weakref.ReferenceError |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
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diff
changeset
|
412 |
|
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Initial QEMU (symbian-qemu-0.9.1-12) import
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changeset
|
413 |
|
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Initial QEMU (symbian-qemu-0.9.1-12) import
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changeset
|
414 |
.. seealso:: |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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parents:
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changeset
|
415 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
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diff
changeset
|
416 |
:pep:`205` - Weak References |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
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parents:
diff
changeset
|
417 |
Written and implemented by Fred L. Drake, Jr. |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
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changeset
|
418 |
|
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Initial QEMU (symbian-qemu-0.9.1-12) import
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diff
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|
419 |
.. ====================================================================== |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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changeset
|
420 |
|
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Initial QEMU (symbian-qemu-0.9.1-12) import
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diff
changeset
|
421 |
|
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Initial QEMU (symbian-qemu-0.9.1-12) import
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diff
changeset
|
422 |
PEP 232: Function Attributes |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
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parents:
diff
changeset
|
423 |
============================ |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
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changeset
|
424 |
|
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Initial QEMU (symbian-qemu-0.9.1-12) import
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diff
changeset
|
425 |
In Python 2.1, functions can now have arbitrary information attached to them. |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
426 |
People were often using docstrings to hold information about functions and |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
427 |
methods, because the ``__doc__`` attribute was the only way of attaching any |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
428 |
information to a function. For example, in the Zope Web application server, |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
429 |
functions are marked as safe for public access by having a docstring, and in |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
430 |
John Aycock's SPARK parsing framework, docstrings hold parts of the BNF grammar |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
431 |
to be parsed. This overloading is unfortunate, since docstrings are really |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
432 |
intended to hold a function's documentation; for example, it means you can't |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
433 |
properly document functions intended for private use in Zope. |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
434 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
435 |
Arbitrary attributes can now be set and retrieved on functions using the regular |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
436 |
Python syntax:: |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
437 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
438 |
def f(): pass |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
439 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
440 |
f.publish = 1 |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
441 |
f.secure = 1 |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
442 |
f.grammar = "A ::= B (C D)*" |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
443 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
444 |
The dictionary containing attributes can be accessed as the function's |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
445 |
:attr:`__dict__`. Unlike the :attr:`__dict__` attribute of class instances, in |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
446 |
functions you can actually assign a new dictionary to :attr:`__dict__`, though |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
447 |
the new value is restricted to a regular Python dictionary; you *can't* be |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
448 |
tricky and set it to a :class:`UserDict` instance, or any other random object |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
449 |
that behaves like a mapping. |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
450 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
451 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
452 |
.. seealso:: |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
453 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
454 |
:pep:`232` - Function Attributes |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
455 |
Written and implemented by Barry Warsaw. |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
456 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
457 |
.. ====================================================================== |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
458 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
459 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
460 |
PEP 235: Importing Modules on Case-Insensitive Platforms |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
461 |
======================================================== |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
462 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
463 |
Some operating systems have filesystems that are case-insensitive, MacOS and |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
464 |
Windows being the primary examples; on these systems, it's impossible to |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
465 |
distinguish the filenames ``FILE.PY`` and ``file.py``, even though they do store |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
466 |
the file's name in its original case (they're case-preserving, too). |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
467 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
468 |
In Python 2.1, the :keyword:`import` statement will work to simulate case- |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
469 |
sensitivity on case-insensitive platforms. Python will now search for the first |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
470 |
case-sensitive match by default, raising an :exc:`ImportError` if no such file |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
471 |
is found, so ``import file`` will not import a module named ``FILE.PY``. Case- |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
472 |
insensitive matching can be requested by setting the :envvar:`PYTHONCASEOK` |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
473 |
environment variable before starting the Python interpreter. |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
474 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
475 |
.. ====================================================================== |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
476 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
477 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
478 |
PEP 217: Interactive Display Hook |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
479 |
================================= |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
480 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
481 |
When using the Python interpreter interactively, the output of commands is |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
482 |
displayed using the built-in :func:`repr` function. In Python 2.1, the variable |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
483 |
:func:`sys.displayhook` can be set to a callable object which will be called |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
484 |
instead of :func:`repr`. For example, you can set it to a special pretty- |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
485 |
printing function:: |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
486 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
487 |
>>> # Create a recursive data structure |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
488 |
... L = [1,2,3] |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
489 |
>>> L.append(L) |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
490 |
>>> L # Show Python's default output |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
491 |
[1, 2, 3, [...]] |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
492 |
>>> # Use pprint.pprint() as the display function |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
493 |
... import sys, pprint |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
494 |
>>> sys.displayhook = pprint.pprint |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
495 |
>>> L |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
496 |
[1, 2, 3, <Recursion on list with id=135143996>] |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
497 |
>>> |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
498 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
499 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
500 |
.. seealso:: |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
501 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
502 |
:pep:`217` - Display Hook for Interactive Use |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
503 |
Written and implemented by Moshe Zadka. |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
504 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
505 |
.. ====================================================================== |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
506 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
507 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
508 |
PEP 208: New Coercion Model |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
509 |
=========================== |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
510 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
511 |
How numeric coercion is done at the C level was significantly modified. This |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
512 |
will only affect the authors of C extensions to Python, allowing them more |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
513 |
flexibility in writing extension types that support numeric operations. |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
514 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
515 |
Extension types can now set the type flag ``Py_TPFLAGS_CHECKTYPES`` in their |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
516 |
``PyTypeObject`` structure to indicate that they support the new coercion model. |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
517 |
In such extension types, the numeric slot functions can no longer assume that |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
518 |
they'll be passed two arguments of the same type; instead they may be passed two |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
519 |
arguments of differing types, and can then perform their own internal coercion. |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
520 |
If the slot function is passed a type it can't handle, it can indicate the |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
521 |
failure by returning a reference to the ``Py_NotImplemented`` singleton value. |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
522 |
The numeric functions of the other type will then be tried, and perhaps they can |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
523 |
handle the operation; if the other type also returns ``Py_NotImplemented``, then |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
524 |
a :exc:`TypeError` will be raised. Numeric methods written in Python can also |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
525 |
return ``Py_NotImplemented``, causing the interpreter to act as if the method |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
526 |
did not exist (perhaps raising a :exc:`TypeError`, perhaps trying another |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
527 |
object's numeric methods). |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
528 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
529 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
530 |
.. seealso:: |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
531 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
532 |
:pep:`208` - Reworking the Coercion Model |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
533 |
Written and implemented by Neil Schemenauer, heavily based upon earlier work by |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
534 |
Marc-André Lemburg. Read this to understand the fine points of how numeric |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
535 |
operations will now be processed at the C level. |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
536 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
537 |
.. ====================================================================== |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
538 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
539 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
540 |
PEP 241: Metadata in Python Packages |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
541 |
==================================== |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
542 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
543 |
A common complaint from Python users is that there's no single catalog of all |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
544 |
the Python modules in existence. T. Middleton's Vaults of Parnassus at |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
545 |
http://www.vex.net/parnassus/ are the largest catalog of Python modules, but |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
546 |
registering software at the Vaults is optional, and many people don't bother. |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
547 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
548 |
As a first small step toward fixing the problem, Python software packaged using |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
549 |
the Distutils :command:`sdist` command will include a file named |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
550 |
:file:`PKG-INFO` containing information about the package such as its name, |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
551 |
version, and author (metadata, in cataloguing terminology). PEP 241 contains |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
552 |
the full list of fields that can be present in the :file:`PKG-INFO` file. As |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
553 |
people began to package their software using Python 2.1, more and more packages |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
554 |
will include metadata, making it possible to build automated cataloguing systems |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
555 |
and experiment with them. With the result experience, perhaps it'll be possible |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
556 |
to design a really good catalog and then build support for it into Python 2.2. |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
557 |
For example, the Distutils :command:`sdist` and :command:`bdist_\*` commands |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
558 |
could support a :option:`upload` option that would automatically upload your |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
559 |
package to a catalog server. |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
560 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
561 |
You can start creating packages containing :file:`PKG-INFO` even if you're not |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
562 |
using Python 2.1, since a new release of the Distutils will be made for users of |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
563 |
earlier Python versions. Version 1.0.2 of the Distutils includes the changes |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
564 |
described in PEP 241, as well as various bugfixes and enhancements. It will be |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
565 |
available from the Distutils SIG at http://www.python.org/sigs/distutils-sig/. |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
566 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
567 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
568 |
.. seealso:: |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
569 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
570 |
:pep:`241` - Metadata for Python Software Packages |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
571 |
Written and implemented by A.M. Kuchling. |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
572 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
573 |
:pep:`243` - Module Repository Upload Mechanism |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
574 |
Written by Sean Reifschneider, this draft PEP describes a proposed mechanism for |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
575 |
uploading Python packages to a central server. |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
576 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
577 |
.. ====================================================================== |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
578 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
579 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
580 |
New and Improved Modules |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
581 |
======================== |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
582 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
583 |
* Ka-Ping Yee contributed two new modules: :mod:`inspect.py`, a module for |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
584 |
getting information about live Python code, and :mod:`pydoc.py`, a module for |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
585 |
interactively converting docstrings to HTML or text. As a bonus, |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
586 |
:file:`Tools/scripts/pydoc`, which is now automatically installed, uses |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
587 |
:mod:`pydoc.py` to display documentation given a Python module, package, or |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
588 |
class name. For example, ``pydoc xml.dom`` displays the following:: |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
589 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
590 |
Python Library Documentation: package xml.dom in xml |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
591 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
592 |
NAME |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
593 |
xml.dom - W3C Document Object Model implementation for Python. |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
594 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
595 |
FILE |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
596 |
/usr/local/lib/python2.1/xml/dom/__init__.pyc |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
597 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
598 |
DESCRIPTION |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
599 |
The Python mapping of the Document Object Model is documented in the |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
600 |
Python Library Reference in the section on the xml.dom package. |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
601 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
602 |
This package contains the following modules: |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
603 |
... |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
604 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
605 |
:file:`pydoc` also includes a Tk-based interactive help browser. :file:`pydoc` |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
606 |
quickly becomes addictive; try it out! |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
607 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
608 |
* Two different modules for unit testing were added to the standard library. |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
609 |
The :mod:`doctest` module, contributed by Tim Peters, provides a testing |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
610 |
framework based on running embedded examples in docstrings and comparing the |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
611 |
results against the expected output. PyUnit, contributed by Steve Purcell, is a |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
612 |
unit testing framework inspired by JUnit, which was in turn an adaptation of |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
613 |
Kent Beck's Smalltalk testing framework. See http://pyunit.sourceforge.net/ for |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
614 |
more information about PyUnit. |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
615 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
616 |
* The :mod:`difflib` module contains a class, :class:`SequenceMatcher`, which |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
617 |
compares two sequences and computes the changes required to transform one |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
618 |
sequence into the other. For example, this module can be used to write a tool |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
619 |
similar to the Unix :program:`diff` program, and in fact the sample program |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
620 |
:file:`Tools/scripts/ndiff.py` demonstrates how to write such a script. |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
621 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
622 |
* :mod:`curses.panel`, a wrapper for the panel library, part of ncurses and of |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
623 |
SYSV curses, was contributed by Thomas Gellekum. The panel library provides |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
624 |
windows with the additional feature of depth. Windows can be moved higher or |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
625 |
lower in the depth ordering, and the panel library figures out where panels |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
626 |
overlap and which sections are visible. |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
627 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
628 |
* The PyXML package has gone through a few releases since Python 2.0, and Python |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
629 |
2.1 includes an updated version of the :mod:`xml` package. Some of the |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
630 |
noteworthy changes include support for Expat 1.2 and later versions, the ability |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
631 |
for Expat parsers to handle files in any encoding supported by Python, and |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
632 |
various bugfixes for SAX, DOM, and the :mod:`minidom` module. |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
633 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
634 |
* Ping also contributed another hook for handling uncaught exceptions. |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
635 |
:func:`sys.excepthook` can be set to a callable object. When an exception isn't |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
636 |
caught by any :keyword:`try`...\ :keyword:`except` blocks, the exception will be |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
637 |
passed to :func:`sys.excepthook`, which can then do whatever it likes. At the |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
638 |
Ninth Python Conference, Ping demonstrated an application for this hook: |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
639 |
printing an extended traceback that not only lists the stack frames, but also |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
640 |
lists the function arguments and the local variables for each frame. |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
641 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
642 |
* Various functions in the :mod:`time` module, such as :func:`asctime` and |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
643 |
:func:`localtime`, require a floating point argument containing the time in |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
644 |
seconds since the epoch. The most common use of these functions is to work with |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
645 |
the current time, so the floating point argument has been made optional; when a |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
646 |
value isn't provided, the current time will be used. For example, log file |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
647 |
entries usually need a string containing the current time; in Python 2.1, |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
648 |
``time.asctime()`` can be used, instead of the lengthier |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
649 |
``time.asctime(time.localtime(time.time()))`` that was previously required. |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
650 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
651 |
This change was proposed and implemented by Thomas Wouters. |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
652 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
653 |
* The :mod:`ftplib` module now defaults to retrieving files in passive mode, |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
654 |
because passive mode is more likely to work from behind a firewall. This |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
655 |
request came from the Debian bug tracking system, since other Debian packages |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
656 |
use :mod:`ftplib` to retrieve files and then don't work from behind a firewall. |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
657 |
It's deemed unlikely that this will cause problems for anyone, because Netscape |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
658 |
defaults to passive mode and few people complain, but if passive mode is |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
659 |
unsuitable for your application or network setup, call :meth:`set_pasv(0)` on |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
660 |
FTP objects to disable passive mode. |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
661 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
662 |
* Support for raw socket access has been added to the :mod:`socket` module, |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
663 |
contributed by Grant Edwards. |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
664 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
665 |
* The :mod:`pstats` module now contains a simple interactive statistics browser |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
666 |
for displaying timing profiles for Python programs, invoked when the module is |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
667 |
run as a script. Contributed by Eric S. Raymond. |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
668 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
669 |
* A new implementation-dependent function, :func:`sys._getframe([depth])`, has |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
670 |
been added to return a given frame object from the current call stack. |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
671 |
:func:`sys._getframe` returns the frame at the top of the call stack; if the |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
672 |
optional integer argument *depth* is supplied, the function returns the frame |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
673 |
that is *depth* calls below the top of the stack. For example, |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
674 |
``sys._getframe(1)`` returns the caller's frame object. |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
675 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
676 |
This function is only present in CPython, not in Jython or the .NET |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
677 |
implementation. Use it for debugging, and resist the temptation to put it into |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
678 |
production code. |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
679 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
680 |
.. ====================================================================== |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
681 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
682 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
683 |
Other Changes and Fixes |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
684 |
======================= |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
685 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
686 |
There were relatively few smaller changes made in Python 2.1 due to the shorter |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
687 |
release cycle. A search through the CVS change logs turns up 117 patches |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
688 |
applied, and 136 bugs fixed; both figures are likely to be underestimates. Some |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
689 |
of the more notable changes are: |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
690 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
691 |
* A specialized object allocator is now optionally available, that should be |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
692 |
faster than the system :func:`malloc` and have less memory overhead. The |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
693 |
allocator uses C's :func:`malloc` function to get large pools of memory, and |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
694 |
then fulfills smaller memory requests from these pools. It can be enabled by |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
695 |
providing the :option:`--with-pymalloc` option to the :program:`configure` |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
696 |
script; see :file:`Objects/obmalloc.c` for the implementation details. |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
697 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
698 |
Authors of C extension modules should test their code with the object allocator |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
699 |
enabled, because some incorrect code may break, causing core dumps at runtime. |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
700 |
There are a bunch of memory allocation functions in Python's C API that have |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
701 |
previously been just aliases for the C library's :func:`malloc` and |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
702 |
:func:`free`, meaning that if you accidentally called mismatched functions, the |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
703 |
error wouldn't be noticeable. When the object allocator is enabled, these |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
704 |
functions aren't aliases of :func:`malloc` and :func:`free` any more, and |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
705 |
calling the wrong function to free memory will get you a core dump. For |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
706 |
example, if memory was allocated using :func:`PyMem_New`, it has to be freed |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
707 |
using :func:`PyMem_Del`, not :func:`free`. A few modules included with Python |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
708 |
fell afoul of this and had to be fixed; doubtless there are more third-party |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
709 |
modules that will have the same problem. |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
710 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
711 |
The object allocator was contributed by Vladimir Marangozov. |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
712 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
713 |
* The speed of line-oriented file I/O has been improved because people often |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
714 |
complain about its lack of speed, and because it's often been used as a naĂ¯ve |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
715 |
benchmark. The :meth:`readline` method of file objects has therefore been |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
716 |
rewritten to be much faster. The exact amount of the speedup will vary from |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
717 |
platform to platform depending on how slow the C library's :func:`getc` was, but |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
718 |
is around 66%, and potentially much faster on some particular operating systems. |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
719 |
Tim Peters did much of the benchmarking and coding for this change, motivated by |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
720 |
a discussion in comp.lang.python. |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
721 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
722 |
A new module and method for file objects was also added, contributed by Jeff |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
723 |
Epler. The new method, :meth:`xreadlines`, is similar to the existing |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
724 |
:func:`xrange` built-in. :func:`xreadlines` returns an opaque sequence object |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
725 |
that only supports being iterated over, reading a line on every iteration but |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
726 |
not reading the entire file into memory as the existing :meth:`readlines` method |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
727 |
does. You'd use it like this:: |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
728 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
729 |
for line in sys.stdin.xreadlines(): |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
730 |
# ... do something for each line ... |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
731 |
... |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
732 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
733 |
For a fuller discussion of the line I/O changes, see the python-dev summary for |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
734 |
January 1-15, 2001 at http://www.python.org/dev/summary/2001-01-1.html. |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
735 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
736 |
* A new method, :meth:`popitem`, was added to dictionaries to enable |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
737 |
destructively iterating through the contents of a dictionary; this can be faster |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
738 |
for large dictionaries because there's no need to construct a list containing |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
739 |
all the keys or values. ``D.popitem()`` removes a random ``(key, value)`` pair |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
740 |
from the dictionary ``D`` and returns it as a 2-tuple. This was implemented |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
741 |
mostly by Tim Peters and Guido van Rossum, after a suggestion and preliminary |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
742 |
patch by Moshe Zadka. |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
743 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
744 |
* Modules can now control which names are imported when ``from module import *`` |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
745 |
is used, by defining an ``__all__`` attribute containing a list of names that |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
746 |
will be imported. One common complaint is that if the module imports other |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
747 |
modules such as :mod:`sys` or :mod:`string`, ``from module import *`` will add |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
748 |
them to the importing module's namespace. To fix this, simply list the public |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
749 |
names in ``__all__``:: |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
750 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
751 |
# List public names |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
752 |
__all__ = ['Database', 'open'] |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
753 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
754 |
A stricter version of this patch was first suggested and implemented by Ben |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
755 |
Wolfson, but after some python-dev discussion, a weaker final version was |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
756 |
checked in. |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
757 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
758 |
* Applying :func:`repr` to strings previously used octal escapes for |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
759 |
non-printable characters; for example, a newline was ``'\012'``. This was a |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
760 |
vestigial trace of Python's C ancestry, but today octal is of very little |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
761 |
practical use. Ka-Ping Yee suggested using hex escapes instead of octal ones, |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
762 |
and using the ``\n``, ``\t``, ``\r`` escapes for the appropriate characters, |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
763 |
and implemented this new formatting. |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
764 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
765 |
* Syntax errors detected at compile-time can now raise exceptions containing the |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
766 |
filename and line number of the error, a pleasant side effect of the compiler |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
767 |
reorganization done by Jeremy Hylton. |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
768 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
769 |
* C extensions which import other modules have been changed to use |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
770 |
:func:`PyImport_ImportModule`, which means that they will use any import hooks |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
771 |
that have been installed. This is also encouraged for third-party extensions |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
772 |
that need to import some other module from C code. |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
773 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
774 |
* The size of the Unicode character database was shrunk by another 340K thanks |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
775 |
to Fredrik Lundh. |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
776 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
777 |
* Some new ports were contributed: MacOS X (by Steven Majewski), Cygwin (by |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
778 |
Jason Tishler); RISCOS (by Dietmar Schwertberger); Unixware 7 (by Billy G. |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
779 |
Allie). |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
780 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
781 |
And there's the usual list of minor bugfixes, minor memory leaks, docstring |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
782 |
edits, and other tweaks, too lengthy to be worth itemizing; see the CVS logs for |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
783 |
the full details if you want them. |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
784 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
785 |
.. ====================================================================== |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
786 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
787 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
788 |
Acknowledgements |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
789 |
================ |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
790 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
791 |
The author would like to thank the following people for offering suggestions on |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
792 |
various drafts of this article: Graeme Cross, David Goodger, Jay Graves, Michael |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
793 |
Hudson, Marc-André Lemburg, Fredrik Lundh, Neil Schemenauer, Thomas Wouters. |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
794 |