[Import-sig] Re: [Python-Dev] Proposal for a modified import mechanism.
Prabhu Ramachandran <firstname.lastname@example.org>
Sun, 11 Nov 2001 10:05:13 +0530
>>>>> "GMcM" == Gordon McMillan <email@example.com> writes:
GMcM> [Prabhu works on knee.py]
>> it also fixes a bug where the parent package is an extension
GMcM> Python provides no support for an extension module being a
GMcM> package parent module. More precisely, I think the fact that
GMcM> an extension module can be made to behave like a package
GMcM> parent module is an accident. There is special code in
GMcM> import for modules named __init__, and the code is bypassed
GMcM> for extension modules.
GMcM> I suspect you'd have to provide a pretty strong
GMcM> justification before this would become supported behavior.
I guess this was unclear. My addition is extremely simple and does
not do anything new. Here is an illustration
>>> import knee
>>> import Numeric.array
Traceback (most recent call last):
File "<stdin>", line 1, in ?
File "/usr/local/lib/python2.1/knee.py", line 17, in import_hook
m = load_tail(q, tail)
File "/usr/local/lib/python2.1/knee.py", line 68, in load_tail
m = import_module(head, mname, m)
File "/usr/local/lib/python2.1/knee.py", line 97, in import_module
parent and parent.__path__)
AttributeError: 'Numeric' module has no attribute '__path__'
Point is, there is a line in knee.py (line 97 that assumes that there
is a __path__ attribute for the passed parent. However, if parent is
an extension module there is none. So I simply modified it. Here is
$ diff knee.py /usr/local/lib/python2.1/knee.py
< except (ImportError, AttributeError):
< # extension modules dont have a __path__ attribute.
< # caching failures.
< sys.modules[fqname] = None
> except ImportError:
In fact that is all I changed in knee.py! Which is why I said the
changes are very small. Maybe I should have shown a patch but the
mail was already long.