[Distutils] how do you express a platform-specific dependency?

[Phillip J. Eby]

At 04:15 PM 5/15/2008 -0600, zooko wrote:
>if sys.platform == 'win32':
>     requirements.append('pywin32')
>
>If you do an install which involves fetching and evaluating the
>setup.py, this will suffice.  What I don't understand is what happens
>if declarative metadata is generated, e.g. a "twisted.egg-info/ 
>requires.txt" file which lists requirements.  Will that file contain
>"pywin32" if Twisted was built on Windows but not if it was built
>elsewhere?  Do those files get transferred around, such as in source
>distributions?

Yes...  but when you test or install from a source distribution, 
those files get rebuilt.  And of course, the binary distributions are 
platform-specific.