RetroSearch Browse

Mon Oct 27 11:50:28 CET 2008 · http://mail.python.org/pipermail/python-dev/2008-October/083134.html

Brett Cannon wrote:
> I just discovered frozen packages set their __path__ simply to their
> name and not to a list as expected (http://bugs.python.org/issue4211).
> This made me think about the 'path' argument to find_module() and
> whether it can be treated as simply a hint or should always be
> seriously looked at.
> 
> Take frozen modules, for instance. If the 'path' argument is meant to
> always be considered then if a frozen module is within a package a
> check should be done to make sure that the parent package is in 'path'
> somewhere. But if it is simply a hint, then 'path' should be ignored
> and whether the module can be found should depend fully on
> imp.is_frozen().
> 
> So, what do people think? Should 'path' for find_module() always be
> taken into consideration, or only when it happens to be convenient?

>From PEP 302:

importer.find_module(fullname, path=None)

    This method will be called with the fully qualified name of the
    module.  If the importer is installed on sys.meta_path, it will
    receive a second argument, which is None for a top-level module, or
    package.__path__ for submodules or subpackages[7].  It should return
    a loader object if the module was found, or None if it wasn't.  If
    find_module() raises an exception, it will be propagated to the
    caller, aborting the import.

[7] The path argument to importer.find_module() is there because the
    pkg.__path__ variable may be needed at this point.  It may either
    come from the actual parent module or be supplied by
    imp.find_module() or the proposed imp.get_loader() function.

Note the first "may" in the footnote. If an importer doesn't need
pkg.__path__ to find submodules then it isn't obliged to use it, but the
import machinery provides it as a convenience.

Cheers,
Nick.

-- 
Nick Coghlan   |   ncoghlan at gmail.com   |   Brisbane, Australia
---------------------------------------------------------------

Home - News ( United States | United Kingdom | Italy | Germany ) - Football scores

Showing content from http://mail.python.org/pipermail/python-dev/2008-October/083134.html below:

[Python-Dev] is the 'path' argument to an importer's find_module() just a hint?