On 17 August 2014 02:11, Donald Stufft email@example.com wrote:
It’s not a preferred separator, it’s use is mostly because of various normalization schemes, particularly Wheel, which will convert a ``-`` to a `` _`` in the version. Right now pip considers them equal because it was causing some breakage with Wheels. This rationale should probably be given in the PEP though.
The original bug report in pip for this was https://github.com/pypa/pip/issues/1150.
Donald, I've added this to the list at https://bitbucket.org/pypa/pypi-metadata-formats/issue/49/address-pep-440-v6... (the comments from Marcus and Paul were already noted).
If you could prepare a patch to clarify those, we can get it merged and published, and I'll accept the PEP. (Since they're just clarifications rather than real changes, I'm actually prepared to accept the PEP now, but I don't believe there's any pressing need for urgency on that front - may as well get the clarifications in first)
Thanks for all your work in finally bringing this to fruition, as well as to all those who contributed to the long migration from the original CPAN style versioning to an approach more in line with the Zen of Python :)