On 2012-06-19, at 11:55 AM, Ethan Furman wrote: > Yury Selivanov wrote: >> Hello, >> The new revision of PEP 362 has been posted: >> http://www.python.org/dev/peps/pep-0362/ >> Summary: >> 1. What was 'Signature.__deepcopy__' is now 'Signature.__copy__'. >> __copy__ creates a shallow copy of Signature, shallow copying its >> Parameters as well. >> 2. 'Signature.format()' was removed. I think we'll add something >> to customize formatting later, in 3.4. Although, Signature still has >> its __str__ method. >> 3. Built-in ('C') functions no longer have mutable '__signature__' >> attribute, that patch was reverted. In the "Design Considerations" >> section we stated clear that we don't support some callables. >> 4. Positions of keyword-only parameters now longer affect equality >> testing of Signatures, i.e. 'foo(*, a, b)' is equal to 'foo(*, b, a)' >> (Thanks to Jim Jewett for pointing that out) >> The only question we have now is: when we do equality test between >> Signatures, should we account for positional-only, var_positional >> and var_keyword arguments names? So that: 'foo(*args)' will >> be equal to 'bar(*arguments)', but not to 'spam(*coordinates:int)' >> (Again, I think that's a Jim's idea) > > There are obviously cases where the names should be considered (such as > foo(source, dest) and bar(dest, source) ) and cases where it should not be > (spam(text, count) and eggs(txt, cnt) )... > > I think the default implementation should be strict (names are considered) as > it is safer to have a false negative than a false positive.
+1 > However, rather than force everyone who is willing to cope with the possible > false positives from rewriting a Signature equality routine that ignores > names, perhaps a method can be added to the class that does so? > > class Signature: > . . . > def equivalent(self, other): > "compares two Signatures for equality (ignores parameter names)" > . . . I don't think that comparing signatures will be a common operation, so maybe we can postpone adding any additional methods for that? - Yury _______________________________________________ Python-Dev mailing list Python-Dev@python.org http://mail.python.org/mailman/listinfo/python-dev Unsubscribe: http://mail.python.org/mailman/options/python-dev/archive%40mail-archive.com
