On 29 January 2014 23:16, Donald Stufft <donald@stufft.io> wrote:
So basically even though the text of the PEP specifically points out that a difference of Wheel and Egg is that Eggs are importable it somehow supports that? Can you point to a single line in the PEP that supports this besides the ones you've added?
I added the clarification based on the facts that: 1. We discussed this extensively before PEP 427 was approved, and this was an accepted feature of the design 2. Root-is-purelib only makes sense in the context of supporting the feature 3. Both ensurepip and virtualenv rely on the feature 4. PEP 453 explicitly documents ensurepip's reliance on the feature, with no caveat about this being unsupported in the spec 5. I wouldn't have accepted PEP 427 if wheels didn't provide a strict superset of the features provided by eggs We make mistakes, and things that were discussed and agreed don't always get properly captured in the corresponding PEPs. When that happens, it's a judgement call as to whether properly documenting that is a new feature requiring a new PEP, or merely a clarification to the existing one. For standard library PEPs, we often don't do either - we just fix the implementation without going back for another round of PEP discussions (for smaller tweaks, sometimes we don't even go back to python-dev and instead just resolve things on the tracker). In this case, as BDFL-Delegate, I decided it was a case that merely called for clarification, because I *know* what spec I accepted, and it was the one where wheels offer all the features that eggs do and more. I added the new text specifically because people like Armin Ronacher and yourself had gained an idea from the PEP text that emphatically does *not* align with the design discussions that occurred prior to the acceptance of the PEP. Now, if you'd like to campaign to *remove* this support, then explain your rationale, and make the case for why you think providing the feature is so dangerous that removing it is worth breaking backwards compatibility over. Regards, Nick. -- Nick Coghlan | ncoghlan@gmail.com | Brisbane, Australia