Merged revisions 66457-66459,66465-66468,66483-66485,66487-66491 via svnmerge from
svn+ssh://pythondev@svn.python.org/python/trunk ........ r66457 | antoine.pitrou | 2008-09-13 15:30:30 -0500 (Sat, 13 Sep 2008) | 5 lines Issue #3850: Misc/find_recursionlimit.py was broken. Reviewed by A.M. Kuchling. ........ r66458 | benjamin.peterson | 2008-09-13 17:54:43 -0500 (Sat, 13 Sep 2008) | 1 line fix a name issue; note all doc files should be encoded in utf8 ........ r66459 | benjamin.peterson | 2008-09-14 11:02:22 -0500 (Sun, 14 Sep 2008) | 1 line clarify that radix for int is not 'guessed' ........ r66465 | skip.montanaro | 2008-09-14 21:03:05 -0500 (Sun, 14 Sep 2008) | 3 lines Review usage. Fix a mistake in the new-style class definition. Add a couple new definitions (CPython and virtual machine). ........ r66466 | skip.montanaro | 2008-09-14 21:19:53 -0500 (Sun, 14 Sep 2008) | 2 lines Pick up a few more definitions from the glossary on the wiki. ........ r66467 | benjamin.peterson | 2008-09-14 21:53:23 -0500 (Sun, 14 Sep 2008) | 1 line mention that object.__init__ no longer takes arbitrary args and kwargs ........ r66468 | andrew.kuchling | 2008-09-15 08:08:32 -0500 (Mon, 15 Sep 2008) | 1 line Rewrite item a bit ........ r66483 | georg.brandl | 2008-09-16 05:17:45 -0500 (Tue, 16 Sep 2008) | 2 lines Fix typo. ........ r66484 | benjamin.peterson | 2008-09-16 16:20:28 -0500 (Tue, 16 Sep 2008) | 2 lines be less wordy ........ r66485 | georg.brandl | 2008-09-17 03:45:54 -0500 (Wed, 17 Sep 2008) | 2 lines #3888: add some deprecated modules in whatsnew. ........ r66487 | skip.montanaro | 2008-09-17 06:50:36 -0500 (Wed, 17 Sep 2008) | 2 lines usage ........ r66488 | andrew.kuchling | 2008-09-17 07:57:04 -0500 (Wed, 17 Sep 2008) | 1 line Markup fixes ........ r66489 | andrew.kuchling | 2008-09-17 07:58:22 -0500 (Wed, 17 Sep 2008) | 2 lines Remove comment about improvement: pystone is about the same, and the improvements seem to be difficult to quantify ........ r66490 | andrew.kuchling | 2008-09-17 08:04:53 -0500 (Wed, 17 Sep 2008) | 1 line Note sqlite3 version; move item ........ r66491 | benjamin.peterson | 2008-09-17 16:54:56 -0500 (Wed, 17 Sep 2008) | 1 line document compileall command flags ........
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Doc/glossary.rst
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Doc/glossary.rst
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@ -9,16 +9,17 @@ Glossary
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.. glossary::
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``>>>``
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The typical Python prompt of the interactive shell. Often seen for code
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examples that can be tried right away in the interpreter.
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The default Python prompt of the interactive shell. Often seen for code
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examples which can be executed interactively in the interpreter.
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``...``
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The typical Python prompt of the interactive shell when entering code for
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an indented code block.
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The default Python prompt of the interactive shell when entering code for
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an indented code block or within a pair of matching left and right
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delimiters (parentheses, square brackets or curly braces).
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2to3
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A tool that tries to convert Python 2.x code to Python 3.x code by
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handling most of the incompatibilites that can be detected by parsing the
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handling most of the incompatibilites which can be detected by parsing the
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source and traversing the parse tree.
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2to3 is available in the standard library as :mod:`lib2to3`; a standalone
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@ -34,15 +35,21 @@ Glossary
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ABC with the :mod:`abc` module.
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argument
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A value passed to a function or method, assigned to a name local to
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the body. A function or method may have both positional arguments and
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keyword arguments in its definition. Positional and keyword arguments
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may be variable-length: ``*`` accepts or passes (if in the function
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definition or call) several positional arguments in a list, while ``**``
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does the same for keyword arguments in a dictionary.
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A value passed to a function or method, assigned to a named local
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variable in the function body. A function or method may have both
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positional arguments and keyword arguments in its definition.
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Positional and keyword arguments may be variable-length: ``*`` accepts
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or passes (if in the function definition or call) several positional
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arguments in a list, while ``**`` does the same for keyword arguments
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in a dictionary.
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Any expression may be used within the argument list, and the evaluated
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value is passed to the local variable.
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attribute
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A value associated with an object which is referenced by name using
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dotted expressions. For example, if an object *o* has an attribute
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*a* it would be referenced as *o.a*.
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BDFL
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Benevolent Dictator For Life, a.k.a. `Guido van Rossum
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@ -53,8 +60,26 @@ Glossary
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of a Python program in the interpreter. The bytecode is also cached in
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``.pyc`` and ``.pyo`` files so that executing the same file is faster the
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second time (recompilation from source to bytecode can be avoided). This
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"intermediate language" is said to run on a "virtual machine" that calls
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the subroutines corresponding to each bytecode.
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"intermediate language" is said to run on a :term:`virtual machine`
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that executes the machine code corresponding to each bytecode.
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class
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A template for creating user-defined objects. Class definitions
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normally contain method definitions which operate on instances of the
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class.
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coercion
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The implicit conversion of an instance of one type to another during an
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operation which involves two arguments of the same type. For example,
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``int(3.15)`` converts the floating point number to the integer ``3``, but
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in ``3+4.5``, each argument is of a different type (one int, one float),
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and both must be converted to the same type before they can be added or it
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will raise a ``TypeError``. Coercion between two operands can be
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performed with the ``coerce`` builtin function; thus, ``3+4.5`` is
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equivalent to calling ``operator.add(*coerce(3, 4.5))`` and results in
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``operator.add(3.0, 4.5)``. Without coercion, all arguments of even
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compatible types would have to be normalized to the same value by the
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programmer, e.g., ``float(3)+4.5`` rather than just ``3+4.5``.
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complex number
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An extension of the familiar real number system in which all numbers are
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@ -69,10 +94,15 @@ Glossary
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it's almost certain you can safely ignore them.
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context manager
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An objects that controls the environment seen in a :keyword:`with`
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An object which controls the environment seen in a :keyword:`with`
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statement by defining :meth:`__enter__` and :meth:`__exit__` methods.
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See :pep:`343`.
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CPython
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The canonical implementation of the Python programming language. The
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term "CPython" is used in contexts when necessary to distinguish this
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implementation from others such as Jython or IronPython.
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decorator
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A function returning another function, usually applied as a function
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transformation using the ``@wrapper`` syntax. Common examples for
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@ -92,7 +122,7 @@ Glossary
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The same concept exists for classes, but is less commonly used there.
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descriptor
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An object that defines the methods :meth:`__get__`, :meth:`__set__`, or
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Any object which defines the methods :meth:`__get__`, :meth:`__set__`, or
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:meth:`__delete__`. When a class attribute is a descriptor, its special
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binding behavior is triggered upon attribute lookup. Normally, using
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*a.b* to get, set or delete an attribute looks up the object named *b* in
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@ -106,20 +136,20 @@ Glossary
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dictionary
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An associative array, where arbitrary keys are mapped to values. The use
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of :class:`dict` much resembles that for :class:`list`, but the keys can
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be any object with a :meth:`__hash__` function, not just integers starting
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from zero. Called a hash in Perl.
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of :class:`dict` closely resembles that for :class:`list`, but the keys can
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be any object with a :meth:`__hash__` function, not just integers.
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Called a hash in Perl.
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docstring
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A docstring ("documentation string") is a string literal that appears as
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the first thing in a class or function suite. While ignored when the
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suite is executed, it is recognized by the compiler and put into the
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:attr:`__doc__` attribute of the class or function. Since it is available
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via introspection, it is the canonical place for documentation of the
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A string literal which appears as the first expression in a class,
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function or module. While ignored when the suite is executed, it is
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recognized by the compiler and put into the :attr:`__doc__` attribute
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of the enclosing class, function or module. Since it is available via
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introspection, it is the canonical place for documentation of the
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object.
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duck-typing
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Pythonic programming style that determines an object's type by inspection
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A pythonic programming style which determines an object's type by inspection
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of its method or attribute signature rather than by explicit relationship
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to some type object ("If it looks like a duck and quacks like a duck, it
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must be a duck.") By emphasizing interfaces rather than specific types,
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@ -134,20 +164,20 @@ Glossary
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style assumes the existence of valid keys or attributes and catches
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exceptions if the assumption proves false. This clean and fast style is
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characterized by the presence of many :keyword:`try` and :keyword:`except`
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statements. The technique contrasts with the :term:`LBYL` style that is
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common in many other languages such as C.
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statements. The technique contrasts with the :term:`LBYL` style
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common to many other languages such as C.
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expression
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A piece of syntax which can be evaluated to some value. In other words,
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an expression is an accumulation of expression elements like literals, names,
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attribute access, operators or function calls that all return a value.
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In contrast to other languages, not all language constructs are expressions,
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but there are also :term:`statement`\s that cannot be used as expressions,
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such as :keyword:`while` or :keyword:`if`. Assignments are also not
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expressions.
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an expression is an accumulation of expression elements like literals,
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names, attribute access, operators or function calls which all return a
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value. In contrast to many other languages, not all language constructs
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are expressions. There are also :term:`statement`\s which cannot be used
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as expressions, such as :keyword:`if`. Assignments are also statements,
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not expressions.
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extension module
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A module written in C, using Python's C API to interact with the core and
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A module written in C or C++, using Python's C API to interact with the core and
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with user code.
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function
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collector that is able to detect and break reference cycles.
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generator
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A function that returns an iterator. It looks like a normal function
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A function which returns an iterator. It looks like a normal function
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except that values are returned to the caller using a :keyword:`yield`
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statement instead of a :keyword:`return` statement. Generator functions
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often contain one or more :keyword:`for` or :keyword:`while` loops that
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often contain one or more :keyword:`for` or :keyword:`while` loops which
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:keyword:`yield` elements back to the caller. The function execution is
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stopped at the :keyword:`yield` keyword (returning the result) and is
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resumed there when the next element is requested by calling the
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See :term:`global interpreter lock`.
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global interpreter lock
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The lock used by Python threads to assure that only one thread can be run
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at a time. This simplifies Python by assuring that no two processes can
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access the same memory at the same time. Locking the entire interpreter
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makes it easier for the interpreter to be multi-threaded, at the expense
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of some parallelism on multi-processor machines. Efforts have been made
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in the past to create a "free-threaded" interpreter (one which locks
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shared data at a much finer granularity), but performance suffered in the
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common single-processor case.
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The lock used by Python threads to assure that only one thread
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executes in the :term:`CPython` :term:`virtual machine` at a time.
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This simplifies the CPython implementation by assuring that no two
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processes can access the same memory at the same time. Locking the
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entire interpreter makes it easier for the interpreter to be
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multi-threaded, at the expense of much of the parallelism afforded by
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multi-processor machines. Efforts have been made in the past to
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create a "free-threaded" interpreter (one which locks shared data at a
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much finer granularity), but so far none have been successful because
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performance suffered in the common single-processor case.
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hashable
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An object is *hashable* if it has a hash value that never changes during
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An object is *hashable* if it has a hash value which never changes during
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its lifetime (it needs a :meth:`__hash__` method), and can be compared to
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other objects (it needs an :meth:`__eq__` or :meth:`__cmp__` method).
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Hashable objects that compare equal must have the same hash value.
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Hashable objects which compare equal must have the same hash value.
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Hashability makes an object usable as a dictionary key and a set member,
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because these data structures use the hash value internally.
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All of Python's immutable built-in objects are hashable, while all mutable
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containers (such as lists or dictionaries) are not. Objects that are
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All of Python's immutable built-in objects are hashable, while no mutable
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containers (such as lists or dictionaries) are. Objects which are
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instances of user-defined classes are hashable by default; they all
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compare unequal, and their hash value is their :func:`id`.
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IDLE
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An Integrated Development Environment for Python. IDLE is a basic editor
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and interpreter environment that ships with the standard distribution of
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and interpreter environment which ships with the standard distribution of
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Python. Good for beginners, it also serves as clear example code for
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those wanting to implement a moderately sophisticated, multi-platform GUI
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application.
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immutable
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An object with fixed value. Immutable objects are numbers, strings or
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tuples (and more). Such an object cannot be altered. A new object has to
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An object with a fixed value. Immutable objects include numbers, strings and
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tuples. Such an object cannot be altered. A new object has to
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be created if a different value has to be stored. They play an important
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role in places where a constant hash value is needed, for example as a key
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in a dictionary.
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:term:`__future__`.
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interactive
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Python has an interactive interpreter which means that you can try out
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things and immediately see their results. Just launch ``python`` with no
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arguments (possibly by selecting it from your computer's main menu). It is
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a very powerful way to test out new ideas or inspect modules and packages
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(remember ``help(x)``).
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Python has an interactive interpreter which means you can enter
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statements and expressions at the interpreter prompt, immediately
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execute them and see their results. Just launch ``python`` with no
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arguments (possibly by selecting it from your computer's main
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menu). It is a very powerful way to test out new ideas or inspect
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modules and packages (remember ``help(x)``).
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interpreted
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Python is an interpreted language, as opposed to a compiled one. This
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means that the source files can be run directly without first creating an
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executable which is then run. Interpreted languages typically have a
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shorter development/debug cycle than compiled ones, though their programs
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generally also run more slowly. See also :term:`interactive`.
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Python is an interpreted language, as opposed to a compiled one,
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though the distinction can be blurry because of the presence of the
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bytecode compiler. This means that source files can be run directly
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without explicitly creating an executable which is then run.
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Interpreted languages typically have a shorter development/debug cycle
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than compiled ones, though their programs generally also run more
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slowly. See also :term:`interactive`.
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iterable
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A container object capable of returning its members one at a
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iterator
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An object representing a stream of data. Repeated calls to the iterator's
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:meth:`__next__` (or passing it to the builtin function) :func:`next`
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method return successive items in the stream. When no more data is
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:meth:`__next__` (or passing it to the builtin function) :func:`next`
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method return successive items in the stream. When no more data are
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available a :exc:`StopIteration` exception is raised instead. At this
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point, the iterator object is exhausted and any further calls to its
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:meth:`__next__` method just raise :exc:`StopIteration` again. Iterators
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are required to have an :meth:`__iter__` method that returns the iterator
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:meth:`next` method just raise :exc:`StopIteration` again. Iterators are
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required to have an :meth:`__iter__` method that returns the iterator
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object itself so every iterator is also iterable and may be used in most
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places where other iterables are accepted. One notable exception is code
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that attempts multiple iteration passes. A container object (such as a
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which attempts multiple iteration passes. A container object (such as a
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:class:`list`) produces a fresh new iterator each time you pass it to the
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:func:`iter` function or use it in a :keyword:`for` loop. Attempting this
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with an iterator will just return the same exhausted iterator object used
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|
@ -315,17 +350,22 @@ Glossary
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pre-conditions before making calls or lookups. This style contrasts with
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the :term:`EAFP` approach and is characterized by the presence of many
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:keyword:`if` statements.
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list
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A built-in Python :term:`sequence`. Despite its name it is more akin
|
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to an array in other languages than to a linked list since access to
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elements are O(1).
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list comprehension
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A compact way to process all or a subset of elements in a sequence and
|
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A compact way to process all or part of the elements in a sequence and
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return a list with the results. ``result = ["0x%02x" % x for x in
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range(256) if x % 2 == 0]`` generates a list of strings containing hex
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numbers (0x..) that are even and in the range from 0 to 255. The
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:keyword:`if` clause is optional. If omitted, all elements in
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``range(256)`` are processed.
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range(256) if x % 2 == 0]`` generates a list of strings containing
|
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even hex numbers (0x..) in the range from 0 to 255. The :keyword:`if`
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clause is optional. If omitted, all elements in ``range(256)`` are
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processed.
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mapping
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A container object (such as :class:`dict`) that supports arbitrary key
|
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A container object (such as :class:`dict`) which supports arbitrary key
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lookups using the special method :meth:`__getitem__`.
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metaclass
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More information can be found in :ref:`metaclasses`.
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method
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A function that is defined inside a class body. If called as an attribute
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A function which is defined inside a class body. If called as an attribute
|
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of an instance of that class, the method will get the instance object as
|
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its first :term:`argument` (which is usually called ``self``).
|
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See :term:`function` and :term:`nested scope`.
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|
@ -352,7 +392,7 @@ Glossary
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also :term:`immutable`.
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named tuple
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Any tuple subclass whose indexable fields are also accessible with
|
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Any tuple subclass whose indexable elements are also accessible using
|
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named attributes (for example, :func:`time.localtime` returns a
|
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tuple-like object where the *year* is accessible either with an
|
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index such as ``t[0]`` or with a named attribute like ``t.tm_year``).
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|
@ -374,7 +414,7 @@ Glossary
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it clear which module implements a function. For instance, writing
|
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:func:`random.seed` or :func:`itertools.izip` makes it clear that those
|
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functions are implemented by the :mod:`random` and :mod:`itertools`
|
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modules respectively.
|
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modules, respectively.
|
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|
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nested scope
|
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The ability to refer to a variable in an enclosing definition. For
|
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|
@ -390,6 +430,13 @@ Glossary
|
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versatile features like :attr:`__slots__`, descriptors, properties,
|
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:meth:`__getattribute__`, class methods, and static methods.
|
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|
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More information can be found in :ref:`newstyle`.
|
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|
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object
|
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Any data with state (attributes or value) and defined behavior
|
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(methods). Also the ultimate base class of any :term:`new-style
|
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class`.
|
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|
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positional argument
|
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The arguments assigned to local names inside a function or method,
|
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determined by the order in which they were given in the call. ``*`` is
|
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|
@ -403,11 +450,12 @@ Glossary
|
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abbreviated "Py3k".
|
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|
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Pythonic
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An idea or piece of code which closely follows the most common idioms of
|
||||
the Python language, rather than implementing code using concepts common
|
||||
in other languages. For example, a common idiom in Python is the :keyword:`for`
|
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loop structure; other languages don't have this easy keyword, so people
|
||||
use a numerical counter instead::
|
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An idea or piece of code which closely follows the most common idioms
|
||||
of the Python language, rather than implementing code using concepts
|
||||
common to other languages. For example, a common idiom in Python is
|
||||
to loop over all elements of an iterable using a :keyword:`for`
|
||||
statement. Many other languages don't have this type of construct, so
|
||||
people unfamiliar with Python sometimes use a numerical counter instead::
|
||||
|
||||
for i in range(len(food)):
|
||||
print(food[i])
|
||||
|
@ -418,11 +466,13 @@ Glossary
|
|||
print(piece)
|
||||
|
||||
reference count
|
||||
The number of places where a certain object is referenced to. When the
|
||||
reference count drops to zero, an object is deallocated. While reference
|
||||
counting is invisible on the Python code level, it is used on the
|
||||
implementation level to keep track of allocated memory.
|
||||
|
||||
The number of references to an object. When the reference count of an
|
||||
object drops to zero, it is deallocated. Reference counting is
|
||||
generally not visible to Python code, but it is a key element of the
|
||||
:term:`CPython` implementation. The :mod:`sys` module defines a
|
||||
:func:`getrefcount` function that programmers can call to return the
|
||||
reference count for a particular object.
|
||||
|
||||
__slots__
|
||||
A declaration inside a class that saves memory by pre-declaring space for
|
||||
instance attributes and eliminating instance dictionaries. Though
|
||||
|
@ -432,7 +482,8 @@ Glossary
|
|||
|
||||
sequence
|
||||
An :term:`iterable` which supports efficient element access using integer
|
||||
indices via the :meth:`__getitem__` and :meth:`__len__` special methods.
|
||||
indices via the :meth:`__getitem__` special method and defines a
|
||||
:meth:`len` method that returns the length of the sequence.
|
||||
Some built-in sequence types are :class:`list`, :class:`str`,
|
||||
:class:`tuple`, and :class:`unicode`. Note that :class:`dict` also
|
||||
supports :meth:`__getitem__` and :meth:`__len__`, but is considered a
|
||||
|
@ -450,10 +501,23 @@ Glossary
|
|||
an :term:`expression` or a one of several constructs with a keyword, such
|
||||
as :keyword:`if`, :keyword:`while` or :keyword:`for`.
|
||||
|
||||
triple-quoted string
|
||||
A string which is bound by three instances of either a quotation mark
|
||||
(") or an apostrophe ('). While they don't provide any functionality
|
||||
not available with single-quoted strings, they are useful for a number
|
||||
of reasons. They allow you to include unescaped single and double
|
||||
quotes within a string and they can span multiple lines without the
|
||||
use of the continuation character, making them especially useful when
|
||||
writing docstrings.
|
||||
|
||||
type
|
||||
The type of a Python object determines what kind of object it is; every
|
||||
object has a type. An object's type is accessible as its
|
||||
:attr:`__class__` attribute or can be retrieved with ``type(obj)``.
|
||||
|
||||
virtual machine
|
||||
A computer defined entirely in software. Python's virtual machine
|
||||
executes the :term:`bytecode` emitted by the bytecode compiler.
|
||||
|
||||
Zen of Python
|
||||
Listing of Python design principles and philosophies that are helpful in
|
||||
|
|
|
@ -79,12 +79,12 @@ flag. Note that *only* doctests will be refactored.
|
|||
The :option:`-v` option enables the output of more information on the
|
||||
translation process.
|
||||
|
||||
When the :option:`-p` is passed to it, 2to3 treats ``print`` as a function
|
||||
instead of a statement. This is useful when ``from __future__ import
|
||||
print_function`` is being used. If this option is not given, the print fixer
|
||||
will surround print calls in an extra set of parentheses because it cannot
|
||||
differentiate between the and print statement with parentheses (such as ``print
|
||||
("a" + "b" + "c")``) and a true function call.
|
||||
When the :option:`-p` is passed, 2to3 treats ``print`` as a function instead of
|
||||
a statement. This is useful when ``from __future__ import print_function`` is
|
||||
being used. If this option is not given, the print fixer will surround print
|
||||
calls in an extra set of parentheses because it cannot differentiate between the
|
||||
and print statement with parentheses (such as ``print ("a" + "b" + "c")``) and a
|
||||
true function call.
|
||||
|
||||
|
||||
:mod:`lib2to3` - 2to3's library
|
||||
|
|
|
@ -359,7 +359,7 @@ in Unix::
|
|||
|
||||
.. method:: defaultdict.__missing__(key)
|
||||
|
||||
If the :attr:`default_factory` attribute is ``None``, this raises an
|
||||
If the :attr:`default_factory` attribute is ``None``, this raises a
|
||||
:exc:`KeyError` exception with the *key* as argument.
|
||||
|
||||
If :attr:`default_factory` is not ``None``, it is called without arguments
|
||||
|
|
|
@ -11,8 +11,13 @@ libraries. These functions compile Python source files in a directory tree,
|
|||
allowing users without permission to write to the libraries to take advantage of
|
||||
cached byte-code files.
|
||||
|
||||
The source file for this module may also be used as a script to compile Python
|
||||
sources in directories named on the command line or in ``sys.path``.
|
||||
This module may also be used as a script (using the :option:`-m` Python flag) to
|
||||
compile Python sources. Directories to recursively traverse (passing
|
||||
:option:`-l` stops the recursive behavior) for sources are listed on the command
|
||||
line. If no arguments are given, the invocation is equivalent to ``-l
|
||||
sys.path``. Printing lists of the files compiled can be disabled with the
|
||||
:option:`-q` flag. In addition, the :option:`-x` option takes a regular
|
||||
expression argument. All files that match the expression will be skipped.
|
||||
|
||||
|
||||
.. function:: compile_dir(dir[, maxlevels[, ddir[, force[, rx[, quiet]]]]])
|
||||
|
|
|
@ -368,7 +368,7 @@ complicated example::
|
|||
As you can see, the :keyword:`finally` clause is executed in any event. The
|
||||
:exc:`TypeError` raised by dividing two strings is not handled by the
|
||||
:keyword:`except` clause and therefore re-raised after the :keyword:`finally`
|
||||
clauses has been executed.
|
||||
clause has been executed.
|
||||
|
||||
In real world applications, the :keyword:`finally` clause is useful for
|
||||
releasing external resources (such as files or network connections), regardless
|
||||
|
|
|
@ -1723,9 +1723,6 @@ Optimizations
|
|||
free lists when garbage-collecting the highest generation of objects.
|
||||
This may return memory to the operating system sooner.
|
||||
|
||||
The net result of the 2.6 optimizations is that Python 2.6 runs the pystone
|
||||
benchmark around XXX% faster than Python 2.5.
|
||||
|
||||
.. ======================================================================
|
||||
|
||||
.. _new-26-interpreter:
|
||||
|
@ -1794,7 +1791,6 @@ changes, or look through the Subversion logs for all the details.
|
|||
:mod:`mimetools`,
|
||||
:mod:`multifile`,
|
||||
:mod:`new`,
|
||||
:mod:`popen2`,
|
||||
:mod:`pure`,
|
||||
:mod:`statvfs`,
|
||||
:mod:`sunaudiodev`,
|
||||
|
@ -1806,12 +1802,10 @@ changes, or look through the Subversion logs for all the details.
|
|||
were applied. (Maintained by Josiah Carlson; see :issue:`1736190` for
|
||||
one patch.)
|
||||
|
||||
.. |uacute| unicode:: 0xA9
|
||||
|
||||
* The :mod:`bsddb` module also has a new maintainer, Jes|uacute|s Cea,
|
||||
and the package is now available as a standalone package.
|
||||
The web page for the package is
|
||||
`www.jcea.es/programacion/pybsddb.htm <http://www.jcea.es/programacion/pybsddb.htm>`__.
|
||||
* The :mod:`bsddb` module also has a new maintainer, Jesús Cea, and the package
|
||||
is now available as a standalone package. The web page for the package is
|
||||
`www.jcea.es/programacion/pybsddb.htm
|
||||
<http://www.jcea.es/programacion/pybsddb.htm>`__.
|
||||
|
||||
* The :mod:`bsddb.dbshelve` module now uses the highest pickling protocol
|
||||
available, instead of restricting itself to protocol 1.
|
||||
|
@ -2134,6 +2128,13 @@ changes, or look through the Subversion logs for all the details.
|
|||
|
||||
(Contributed by Christian Heimes and Mark Dickinson.)
|
||||
|
||||
* The :mod:`MimeWriter` module and :mod:`mimify` module
|
||||
have been deprecated; use the :mod:`email`
|
||||
package instead.
|
||||
|
||||
* The :mod:`md5` module has been deprecated; use the :mod:`hashlib` module
|
||||
instead.
|
||||
|
||||
* :class:`mmap` objects now have a :meth:`rfind` method that searches for a
|
||||
substring beginning at the end of the string and searching
|
||||
backwards. The :meth:`find` method also gained an *end* parameter
|
||||
|
@ -2216,6 +2217,9 @@ changes, or look through the Subversion logs for all the details.
|
|||
and can optionally take new command-line arguments for the program.
|
||||
(Contributed by Rocky Bernstein; :issue:`1393667`.)
|
||||
|
||||
* The :mod:`posixfile` module has been deprecated; :func:`fcntl.lockf`
|
||||
provides better locking.
|
||||
|
||||
The :func:`post_mortem` function, used to begin debugging a
|
||||
traceback, will now use the traceback returned by :func:`sys.exc_info`
|
||||
if no traceback is supplied. (Contributed by Facundo Batista;
|
||||
|
@ -2226,6 +2230,9 @@ changes, or look through the Subversion logs for all the details.
|
|||
opcodes, returning a shorter pickle that contains the same data structure.
|
||||
(Contributed by Raymond Hettinger.)
|
||||
|
||||
* The :mod:`popen2` module has been deprecated; use the :mod:`subprocess`
|
||||
module.
|
||||
|
||||
* A :func:`get_data` function was added to the :mod:`pkgutil`
|
||||
module that returns the contents of resource files included
|
||||
with an installed Python package. For example::
|
||||
|
@ -2305,6 +2312,9 @@ changes, or look through the Subversion logs for all the details.
|
|||
* The :mod:`sets` module has been deprecated; it's better to
|
||||
use the built-in :class:`set` and :class:`frozenset` types.
|
||||
|
||||
* The :mod:`sha` module has been deprecated; use the :mod:`hashlib` module
|
||||
instead.
|
||||
|
||||
* The :func:`shutil.copytree` function now has an optional *ignore* argument
|
||||
that takes a callable object. This callable will receive each directory path
|
||||
and a list of the directory's contents, and returns a list of names that
|
||||
|
@ -2390,6 +2400,10 @@ changes, or look through the Subversion logs for all the details.
|
|||
(Contributed by Pedro Werneck and Jeffrey Yasskin;
|
||||
:issue:`742598`, :issue:`1193577`.)
|
||||
|
||||
* The :mod:`sqlite3` module, maintained by Gerhard Haering,
|
||||
has been updated from version 2.3.2 in Python 2.5 to
|
||||
version 2.4.1.
|
||||
|
||||
* The :mod:`struct` module now supports the C99 :ctype:`_Bool` type,
|
||||
using the format character ``'?'``.
|
||||
(Contributed by David Remahl.)
|
||||
|
@ -3158,6 +3172,13 @@ that may require changes to your code:
|
|||
before adding elements from the iterable. This change makes the
|
||||
behavior match ``list.__init__()``.
|
||||
|
||||
* :meth:`object.__init__` previously accepted arbitrary arguments and
|
||||
keyword arguments, ignoring them. In Python 2.6, this is no longer
|
||||
allowed and will result in a :exc:`TypeError`. This will affect
|
||||
:meth:`__init__` methods that end up calling the corresponding
|
||||
method on :class:`object` (perhaps through using :func:`super`).
|
||||
See :issue:`1683368` for discussion.
|
||||
|
||||
* The :class:`Decimal` constructor now accepts leading and trailing
|
||||
whitespace when passed a string. Previously it would raise an
|
||||
:exc:`InvalidOperation` exception. On the other hand, the
|
||||
|
|
|
@ -1,22 +1,32 @@
|
|||
#! /usr/bin/env python
|
||||
"""Find the maximum recursion limit that prevents core dumps
|
||||
"""Find the maximum recursion limit that prevents interpreter termination.
|
||||
|
||||
This script finds the maximum safe recursion limit on a particular
|
||||
platform. If you need to change the recursion limit on your system,
|
||||
this script will tell you a safe upper bound. To use the new limit,
|
||||
call sys.setrecursionlimit.
|
||||
call sys.setrecursionlimit().
|
||||
|
||||
This module implements several ways to create infinite recursion in
|
||||
Python. Different implementations end up pushing different numbers of
|
||||
C stack frames, depending on how many calls through Python's abstract
|
||||
C API occur.
|
||||
|
||||
After each round of tests, it prints a message
|
||||
Limit of NNNN is fine.
|
||||
After each round of tests, it prints a message:
|
||||
"Limit of NNNN is fine".
|
||||
|
||||
It ends when Python causes a segmentation fault because the limit is
|
||||
too high. On platforms like Mac and Windows, it should exit with a
|
||||
MemoryError.
|
||||
The highest printed value of "NNNN" is therefore the highest potentially
|
||||
safe limit for your system (which depends on the OS, architecture, but also
|
||||
the compilation flags). Please note that it is practically impossible to
|
||||
test all possible recursion paths in the interpreter, so the results of
|
||||
this test should not be trusted blindly -- although they give a good hint
|
||||
of which values are reasonable.
|
||||
|
||||
NOTE: When the C stack space allocated by your system is exceeded due
|
||||
to excessive recursion, exact behaviour depends on the platform, although
|
||||
the interpreter will always fail in a likely brutal way: either a
|
||||
segmentation fault, a MemoryError, or just a silent abort.
|
||||
|
||||
NB: A program that does not use __methods__ can set a higher limit.
|
||||
"""
|
||||
|
||||
import sys
|
||||
|
@ -87,7 +97,10 @@ def check_limit(n, test_func_name):
|
|||
test_func = globals()[test_func_name]
|
||||
try:
|
||||
test_func()
|
||||
except RuntimeError:
|
||||
# AttributeError can be raised because of the way e.g. PyDict_GetItem()
|
||||
# silences all exceptions and returns NULL, which is usually interpreted
|
||||
# as "missing attribute".
|
||||
except (RuntimeError, AttributeError):
|
||||
pass
|
||||
else:
|
||||
print("Yikes!")
|
||||
|
|
Loading…
Reference in New Issue