Merged revisions 69417,69435,69442 via svnmerge from

svn+ssh://pythondev@svn.python.org/python/trunk

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  r69417 | benjamin.peterson | 2009-02-08 00:01:19 +0100 (So, 08 Feb 2009) | 1 line

  document individual 2to3 fixers
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  r69435 | benjamin.peterson | 2009-02-08 15:38:13 +0100 (So, 08 Feb 2009) | 1 line

  document numliterals fixer
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  r69442 | benjamin.peterson | 2009-02-08 16:14:57 +0100 (So, 08 Feb 2009) | 1 line

  a few edits and typos
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This commit is contained in:
Georg Brandl 2009-10-27 13:31:19 +00:00
parent 9903bc97e2
commit 27e872389b
2 changed files with 258 additions and 4 deletions

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@ -14,6 +14,8 @@ adapted to custom applications in which Python code needs to be edited
automatically.
.. _2to3-using:
Using 2to3
----------
@ -52,10 +54,10 @@ After transformation, :file:`example.py` looks like this::
Comments and exact indentation are preserved throughout the translation process.
By default, 2to3 runs a set of predefined fixers. The :option:`-l` flag lists
all available fixers. An explicit set of fixers to run can be given with
:option:`-f`. Likewise the :option:`-x` explicitly disables a fixer. The
following example runs only the ``imports`` and ``has_key`` fixers::
By default, 2to3 runs a set of :ref:`predefined fixers <2to3-fixers>`. The
:option:`-l` flag lists all available fixers. An explicit set of fixers to run
can be given with :option:`-f`. Likewise the :option:`-x` explicitly disables a
fixer. The following example runs only the ``imports`` and ``has_key`` fixers::
$ 2to3 -f imports -f has_key example.py
@ -85,6 +87,257 @@ The :option:`-v` option enables output of more information on the translation
process.
.. _2to3-fixers:
Fixers
------
Each step of tranforming code is encapsulated in a fixer. The command ``2to3
-l`` lists them. As :ref:`documented above <2to3-using>`, each can be turned on
and off individually. They are described here in more detail.
.. 2to3fixer:: apply
Removes usage of :func:`apply`. For example ``apply(function, *args,
**kwargs)`` is converted to ``function(*args, **kwargs)``.
.. 2to3fixer:: basestring
Converts :class:`basestring` to :class:`str`.
.. 2to3fixer:: buffer
Converts :class:`buffer` to :class:`memoryview`. This fixer is optional
because the :class:`memoryview` API is similar but not exactly the same as
that of :class:`buffer`.
.. 2to3fixer:: callable
Converts ``callable(x)`` to ``hasattr(x, "__call_")``.
.. 2to3fixer:: dict
Fixes dictionary iteration methods. :meth:`dict.iteritems` is converted to
:meth:`dict.items`, :meth:`dict.iterkeys` to :meth:`dict.keys`, and
:meth:`dict.itervalues` to :meth:`dict.values`. It also wraps existing
usages of :meth:`dict.items`, :meth:`dict.keys`, and :meth:`dict.values` in a
call to :class:`list`.
.. 2to3fixer:: except
Converts ``except X, T`` to ``except X as T``.
.. 2to3fixer:: exec
Converts the :keyword:`exec` statement to the :func:`exec` function.
.. 2to3fixer:: execfile
Removes usage of :func:`execfile`. The argument to :func:`execfile` is
wrapped in calls to :func:`open`, :func:`compile`, and :func:`exec`.
.. 2to3fixer:: filter
Wraps :func:`filter` usage in a :class:`list` call.
.. 2to3fixer:: funcattrs
Fixes function attributes that have been renamed. For example,
``my_function.func_closure`` is converted to ``my_function.__closure__``.
.. 2to3fixer:: future
Removes ``from __future__ import new_feature`` statements.
.. 2to3fixer:: getcwdu
Renames :func:`os.getcwdu` to :func:`os.getcwd`.
.. 2to3fixer:: has_key
Changes ``dict.has_key(key)`` to ``key in dict``.
.. 2to3fixer:: idioms
This optional fixer preforms several transformations that make Python code
more idiomatic. Type comparisions like ``type(x) is SomeClass`` and
``type(x) == SomeClass`` are converted to ``isinstance(x, SomeClass)``.
``while 1`` becomes ``while True``. This fixer also tries to make use of
:func:`sorted` in appropiate places. For example, this block ::
L = list(some_iterable)
L.sort()
is changed to ::
L = sorted(some_iterable)
.. 2to3fixer:: import
Detects sibling imports and converts them to relative imports.
.. 2to3fixer:: imports
Handles module renames in the standard library.
.. 2to3fixer:: imports2
Handles other modules renames in the standard library. It is separate from
the :2to3fixer:`imports` fixer only because of technical limitations.
.. 2to3fixer:: input
Converts ``input(prompt)`` to ``eval(input(prompt))``
.. 2to3fixer:: intern
Converts :func:`intern` to :func:`sys.intern`.
.. 2to3fixer:: isinstance
Fixes duplicate types in the second argument of :func:`isinstance`. For
example, ``isinstance(x, (int, int))`` is converted to ``isinstance(x,
(int))``.
.. 2to3fixer:: itertools_imports
Removes imports of :func:`itertools.ifilter`, :func:`itertools.izip`, and
:func:`itertools.imap`. Imports of :func:`itertools.ifilterfalse` are also
changed to :func:`itertools.filterfalse`.
.. 2to3fixer:: itertools
Changes usage of :func:`itertools.ifilter`, :func:`itertools.izip`, and
:func:`itertools.imap` to their builtin equivalents.
:func:`itertools.ifilterfalse` is changed to :func:`itertools.filterfalse`.
.. 2to3fixer:: long
Strips the ``L`` prefix on long literals and renames :class:`long` to
:class:`int`.
.. 2to3fixer:: map
Wraps :func:`map` in a :class:`list` call. It also changes ``map(None, x)``
to ``list(x)``. Using ``from future_builtins import map`` disables this
fixer.
.. 2to3fixer:: metaclass
Converts the old metaclass syntax (``__metaclass__ = Meta`` in the class
body) to the new (``class X(metaclass=Meta)``).
.. 2to3fixer:: methodattrs
Fixes old method attribute names. For example, ``meth.im_func`` is converted
to ``meth.__func__``.
.. 2to3fixer:: ne
Converts the old not-equal syntax, ``<>``, to ``!=``.
.. 2to3fixer:: next
Converts the use of iterator's :meth:`next` methods to the :func:`next`
function. It also renames :meth:`next` methods to :meth:`~object.__next__`.
.. 2to3fixer:: nonzero
Renames :meth:`~object.__nonzero__` to :meth:`~object.__bool__`.
.. 2to3fixer:: numliterals
Converts octal literals into the new syntax.
.. 2to3fixer:: paren
Add extra parenthesis where they are required in list comprehensions. For
example, ``[x for x in 1, 2]`` becomes ``[x for x in (1, 2)]``.
.. 2to3fixer:: print
Converts the :keyword:`print` statement to the :func:`print` function.
.. 2to3fixer:: raises
Converts ``raise E, V`` to ``raise E(V)``, and ``raise E, V, T`` to ``raise
E(V).with_traceback(T)``. If ``E`` is a tuple, the translation will be
incorrect because substituting tuples for exceptions has been removed in 3.0.
.. 2to3fixer:: raw_input
Converts :func:`raw_input` to :func:`input`.
.. 2to3fixer:: reduce
Handles the move of :func:`reduce` to :func:`functools.reduce`.
.. 2to3fixer:: renames
Changes :data:`sys.maxint` to :data:`sys.maxsize`.
.. 2to3fixer:: repr
Replaces backtick repr with the :func:`repr` function.
.. 2to3fixer:: set_literal
Replaces use of the :class:`set` constructor with set literals. This fixer
is optional.
.. 2to3fixer:: standard_error
Renames :exc:`StandardError` to :exc:`Exception`.
.. 2to3fixer:: sys_exc
Changes the deprecated :data:`sys.exc_value`, :data:`sys.exc_type`,
:data:`sys.exc_traceback` to use :func:`sys.exc_info`.
.. 2to3fixer:: throw
Fixes the API change in generator's :meth:`throw` method.
.. 2to3fixer:: tuple_params
Removes implicit tuple parameter unpacking. This fixer inserts temporary
variables.
.. 2to3fixer:: types
Fixes code broken from the removal of some members in the :mod:`types`
module.
.. 2to3fixer:: unicode
Renames :class:`unicode` to :class:`str`.
.. 2to3fixer:: urllib
Handles the rename of :mod:`urllib` and :mod:`urllib2` to the :mod:`urllib`
package.
.. 2to3fixer:: ws_comma
Removes excess whitespace from comma separated items. This fixer is
optional.
.. 2to3fixer:: xrange
Renames :func:`xrange` to :func:`range` and wraps existing :func:`range`
calls with :class:`list`.
.. 2to3fixer:: xreadlines
Changes ``for x in file.xreadlines()`` to ``for x in file``.
.. 2to3fixer:: zip
Wraps :func:`zip` usage in a :class:`list` call. This is disabled when
``from future_builtins import zip`` appears.
:mod:`lib2to3` - 2to3's library
-------------------------------

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@ -135,3 +135,4 @@ def setup(app):
app.add_builder(suspicious.CheckSuspiciousMarkupBuilder)
app.add_description_unit('opcode', 'opcode', '%s (opcode)',
parse_opcode_signature)
app.add_description_unit('2to3fixer', '2to3fixer', '%s (2to3 fixer)')