This issue will track implementation ofPEP 362 functionality.

Signature and signature are two variable names that differ only in case.To avoid confusion, I recommend one of the names should be changed.

Well, 'Signature' class is unlikely to be used very frequently.  So I think it's fine.

Yes, it seems quite common to me to have a class called Thing and instances named thing.  Unless it makes the code wrap better, using real names like signature instead of for example sig is recommended byPEP 8.

Attaching a patch that implements the latest version of the PEP.Quick summary:1. Ditched Signature.name & Signature.qualname2. Added Signature.__eq__ and __ne__3. signature() supports classes, metaclasses, decorated stuff, partials, methods, classmethods, callable objects etc4. signature() does a deepcopy of __signature__ attribute ifthere is one5. No implicit caching anywhere6. Signature.format(...) and Signature.__str__7. Signature.bind_partial

Attaching the new version of the patch.Summary:1. 'is_*' family was replaced with 'Parameter.kind'2. 'signature()' function was updated to check for '__wrapped__' attribute in all callables3. 'is_implemented' -> 'implemented'4. Added support for POSITIONAL_ONLY parameters (in 'bind()')

One small thing: can we find a name for the function that starts with a verb?  It’s the recommended naming style for functions, and would help making a difference between the class and the function.  I also expect people to use “signature” and “sig” for their instances.

New version (pep363.4.patch)Summary:1. Removed 'Signature.implemented'2. No more patching built-ins - no issues with shared interpreters3. Removed 'Signature.format()'. If needed we'll reintroduce it in 3.4 (although we still have 'Signature.__str__')4. Signature now implements just __copy__ - creates a shallow copy (__deepcopy__ has been removed, as it wasn't deep)5. Signature.__eq__ fixed to ignore order of keyword-only arguments.Thanks and please review!

Eric,I personally prefer simple 'signature()' more than 'get_signature()'.  But I'll ask this question on python-dev on the next PEP update.

New patch (pep362.5.patch)Fixed a bug in BoundArguments.args & BoundArguments.kwargs

I left a few comments on rietveld.The '\' is sometimes used where not necessary and the preferred way to write conditions on multiple lines is:(foo == bar and bar == baz and baz == asd)rather thanfoo == bar \    and bar == baz \    and baz == asdHave you measured the coverage of the tests?

New patch -pep362.6.patchEzio,I've eliminated almost all '\'.Test coverage is now almost 100%.

New patch -pep362.7.patchSummary:1. Signature & Parameter objects are now immutable2. Signature.replace() and Parameter.replace()3. Signature has a new default constructor, whichaccepts parameters list and a return_annotation; anda new 'from_function', which create a Signature objectfor the passed function.4. Parameter.__str__The implementation has 100% test coverage and is stable.Please review.Thanks!

New patch -pep362.8.patchOne big change (Guido's request) - No more AttributeErrors on missing Parameter.default of Signature.return_annotation.  They now will be set to Parameter.empty & Signature.empty correspondingly.

New changesetd892bf410478 by Larry Hastings in branch 'default':Issue#15008: ImplementPEP 362 "Signature Objects".http://hg.python.org/cpython/rev/d892bf410478

Are we going to get documentation?

Benjamin:http://bugs.python.org/issue15151