changeset: 78388:083534cd7874 user: Brett Cannon date: Thu Aug 02 17:50:06 2012 -0400 files: Doc/library/importlib.rst Doc/whatsnew/3.3.rst description: Update the What's New details for importlib based on doc/ABC changes. diff -r 0a4c7a1e53f2 -r 083534cd7874 Doc/library/importlib.rst --- a/Doc/library/importlib.rst Thu Aug 02 17:35:34 2012 -0400 +++ b/Doc/library/importlib.rst Thu Aug 02 17:50:06 2012 -0400 @@ -141,9 +141,10 @@ longer requires implementation of a ``find_module()`` method. -.. class:: MetaPathFinder(Finder) +.. class:: MetaPathFinder - An abstract base class representing a :term:`meta path finder`. + An abstract base class representing a :term:`meta path finder` and + inheriting from :class:`Finder`. .. versionadded:: 3.3 @@ -156,9 +157,10 @@ package. If a loader cannot be found, ``None`` is returned. -.. class:: PathEntryFinder(Finder) +.. class:: PathEntryFinder - An abstract base class representing a :term:`path entry finder`. + An abstract base class representing a :term:`path entry finder` and + inheriting from :class:`Finder`. .. versionadded:: 3.3 diff -r 0a4c7a1e53f2 -r 083534cd7874 Doc/whatsnew/3.3.rst --- a/Doc/whatsnew/3.3.rst Thu Aug 02 17:35:34 2012 -0400 +++ b/Doc/whatsnew/3.3.rst Thu Aug 02 17:50:06 2012 -0400 @@ -519,7 +519,15 @@ making the import statement work. That means the various importers that were once implicit are now fully exposed as part of the :mod:`importlib` package. -In terms of finders, * :class:`importlib.machinery.FileFinder` exposes the +The abstract base classes defined in :mod:`importlib.abc` have been expanded +to properly delineate between :term:`meta path finders ` +and :term:`path entry finders ` by introducing +:class:`importlib.abc.MetaPathFinder` and +:class:`importlib.abc.PathEntryFinder`, respectively. The old ABC of +:class:`importlib.abc.Finder` is now only provided for backwards-compatibility +and does not enforce any method requirements. + +In terms of finders, :class:`importlib.machinery.FileFinder` exposes the mechanism used to search for source and bytecode files of a module. Previously this class was an implicit member of :attr:`sys.path_hooks`. @@ -547,10 +555,10 @@ Beyond the expanse of what :mod:`importlib` now exposes, there are other visible changes to import. The biggest is that :attr:`sys.meta_path` and -:attr:`sys.path_hooks` now store all of the finders used by import explicitly. -Previously the finders were implicit and hidden within the C code of import -instead of being directly exposed. This means that one can now easily remove or -change the order of the various finders to fit one's needs. +:attr:`sys.path_hooks` now store all of the meta path finders and path entry +hooks used by import. Previously the finders were implicit and hidden within +the C code of import instead of being directly exposed. This means that one can +now easily remove or change the order of the various finders to fit one's needs. Another change is that all modules have a ``__loader__`` attribute, storing the loader used to create the module. :pep:`302` has been updated to make this @@ -1733,6 +1741,12 @@ both the modification time and size of the source file the bytecode file was compiled from. +* :class:`importlib.abc.Finder` no longer specifies a `find_module()` abstract + method that must be implemented. If you were relying on subclasses to + implement that method, make sure to check for the method's existence first. + You will probably want to check for `find_loader()` first, though, in the + case of working with :term:`path entry finders `. + * :mod:`pkgutil` has been converted to use :mod:`importlib` internally. This eliminates many edge cases where the old behaviour of the PEP 302 import emulation failed to match the behaviour of the real import system. The