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diff --git a/Python/Dependencies/future-0.18.2/docs/older_interfaces.rst b/Python/Dependencies/future-0.18.2/docs/older_interfaces.rst deleted file mode 100644 index 546f92b..0000000 --- a/Python/Dependencies/future-0.18.2/docs/older_interfaces.rst +++ /dev/null @@ -1,141 +0,0 @@ -.. _older-standard-library-interfaces: - -Older interfaces -~~~~~~~~~~~~~~~~ - -In addition to the direct and ``install_aliases()`` interfaces (described in -:ref:`standard-library-imports`), ``future`` supports four other interfaces to -the reorganized standard library. This is largely for historical reasons (for -versions prior to 0.14). - - -``future.moves`` interface -__________________________ - -The ``future.moves`` interface avoids import hooks. It may therefore be more -robust, at the cost of less idiomatic code. Use it as follows:: - - from future.moves import queue - from future.moves import socketserver - from future.moves.http.client import HTTPConnection - # etc. - -If you wish to achieve the effect of a two-level import such as this:: - - import http.client - -portably on both Python 2 and Python 3, note that Python currently does not -support syntax like this:: - - from future.moves import http.client - -One workaround is to replace the dot with an underscore:: - - import future.moves.http.client as http_client - - -Comparing future.moves and six.moves -++++++++++++++++++++++++++++++++++++ - -``future.moves`` and ``six.moves`` provide a similar Python 3-style -interface to the native standard library module definitions. - -The major difference is that the ``future.moves`` package is a real Python package -(``future/moves/__init__.py``) with real modules provided as ``.py`` files, whereas -``six.moves`` constructs fake ``_LazyModule`` module objects within the Python -code and injects them into the ``sys.modules`` cache. - -The advantage of ``six.moves`` is that the code fits in a single module that can be -copied into a project that seeks to eliminate external dependencies. - -The advantage of ``future.moves`` is that it is likely to be more robust in the -face of magic like Django's auto-reloader and tools like ``py2exe`` and -``cx_freeze``. See issues #51, #53, #56, and #63 in the ``six`` project for -more detail of bugs related to the ``six.moves`` approach. - - -``import_`` and ``from_import`` functions -_________________________________________ - -The functional interface is to use the ``import_`` and ``from_import`` -functions from ``future.standard_library`` as follows:: - - from future.standard_library import import_, from_import - - http = import_('http.client') - urllib = import_('urllib.request') - - urlopen, urlsplit = from_import('urllib.request', 'urlopen', 'urlsplit') - -This interface also works with two-level imports. - - -Context-manager for import hooks -________________________________ - -The context-manager interface is via a context-manager called ``hooks``:: - - from future.standard_library import hooks - with hooks(): - import socketserver - import queue - import configparser - import test.support - import html.parser - from collections import UserList - from itertools import filterfalse, zip_longest - from http.client import HttpConnection - import urllib.request - # and other moved modules and definitions - -This interface is straightforward and effective, using PEP 302 import -hooks. However, there are reports that this sometimes leads to problems -(see issue #238). Until this is resolved, it is probably safer to use direct -imports or one of the other import mechanisms listed above. - - -install_hooks() call (deprecated) -_________________________________ - -The last interface to the reorganized standard library is via a call to -``install_hooks()``:: - - from future import standard_library - standard_library.install_hooks() - - import urllib - f = urllib.request.urlopen('http://www.python.org/') - - standard_library.remove_hooks() - -If you use this interface, it is recommended to disable the import hooks again -after use by calling ``remove_hooks()``, in order to prevent the futurized -modules from being invoked inadvertently by other modules. (Python does not -automatically disable import hooks at the end of a module, but keeps them -active for the life of a process unless removed.) - -.. The call to ``scrub_future_sys_modules()`` removes any modules from the -.. ``sys.modules`` cache (on Py2 only) that have Py3-style names, like ``http.client``. -.. This can prevent libraries that have their own Py2/3 compatibility code from -.. importing the ``future.moves`` or ``future.backports`` modules unintentionally. -.. Code such as this will then fall through to using the Py2 standard library -.. modules on Py2:: -.. -.. try: -.. from http.client import HTTPConnection -.. except ImportError: -.. from httplib import HTTPConnection -.. -.. **Requests**: The above snippet is from the `requests -.. <http://docs.python-requests.org>`_ library. As of v0.12, the -.. ``future.standard_library`` import hooks are compatible with Requests. - - -.. If you wish to avoid changing every reference of ``http.client`` to -.. ``http_client`` in your code, an alternative is this:: -.. -.. from future.standard_library import http -.. from future.standard_library.http import client as _client -.. http.client = client - -.. but it has the advantage that it can be used by automatic translation scripts such as ``futurize`` and ``pasteurize``. |