[Python-Dev] new import hooks & zip import

[Skip Montanaro]

    Just> Thorough review would be very welcome.

Scanning the patch summary I see:

    sys.path_hooks is a list of callable objects that take 
    a string as their only argument. A hook will be called 
    with a sys.path or pkg.__path__ item. It should return 
    an "importer" object (see below), or raise ImportError 
    or return None if it can't deal with the path item. By 
    default, sys.path_hooks only contains the zipimporter 
    type, if the zipimport module is available. 

Why have it raise ImportError or return None if it can't deal with the path
item?  Shouldn't there be only one way to report failure?  (Or do I misread
your explanation?)

Skip