[Python-Dev] Fix import errors to have data

[Thomas Heller]

Jim Fulton <jim at zope.com> writes:

> Tim Peters wrote:
>> [Jim Fulton]
>> ...
>>
>>>No, it won't.  For example, suppose foo imports B. B tries to import
>>>C, but fails.  B is now broken, but it is still importable.  Actually,
>>>both foo and B can be imported without errors, even though they are
>>>broken.
>> Then you're proposing a way for a highly knowledgable user to
>> anticipate, and partially worm around,  that Python leaves behind
>> insane module objects in sys.modules.
>
> No.  I'm proposing a way for a Python developer to detect the
> presence or absence of a module.
>
> Hm, perhaps it would be better to provide an API (if there isn't one
> already) to test whether a module is present.

Doesn't imp.find_module do this? On Windows:

>>> import imp
>>> imp.find_module("termios")
Traceback (most recent call last):
  File "<stdin>", line 1, in ?
ImportError: No module named termios
>>> imp.find_module("pty")
(<open file 'c:\python23\lib\pty.py', mode 'U' at 0x00981760>, 'c:\\python23\\lib\\pty.py', ('.py',
>>> ^Z

Thomas