[Python-ideas] PEP 484 evolution

[Terry Reedy]

On 3/18/2016 3:09 PM, Guido van Rossum wrote:
> It's a mix. The list of things I definitely want to get to is now
> here: https://github.com/python/typing/milestones/3.5.2

#2: backport aab2c59 to python2/typing.py

I believe you are referring to a back-compatibility module on PyPI.  If 
so, this is out-of-scope for python-ideas.  The only connection with 
3.5.2 is that 2.7.12 should come out about the same time.

#3, #1: many parameters require long comment signature?

These are a question and possible solution for the type comments 
intended for 2.7 (though allowed, I believe, in 3.5 and earlier with the 
back-compatibility module).  The issue: some functions have so many 
parameters that a type comment will not fit on one line.  A proposal 
discussed here before is multiline type comments.  The alternate 
solution is to allow '...' as an abbreviation.

My very slight objection is that this will mean that the type comment no 
longer matches the function signature above.  The counter-argument is 
that duplicating a long parameter type list, especially when one only 
cares about typing the return type, is obnoxious.  I presume this 
proposal is based on problems with real code.  + something.

I do not understand, in #3, "Would it be valid to annotate just a few 
argument [and use ... also, I presume]? and "Yes".  What would it look 
like?  Is that part of #1?

#4 Ambiguity of "Z = Dict[T, int]".

I don't understand enough to understand the 2nd interpretation, so 
'pass'.  Ambiguity is bad, though.

#5 A proposal to allow 'Type[T]'? Where "T = TypeVar['T']"?

Just unpostponed from last May.

#6 "What does it mean to inherit from a generic type without specifying 
type parameters?"

I am not clear on what patch is being proposed.  This seems to still be 
in ideas stage.

#7 Allow @overload in implementation as well as stub files.

You originally rejected this, then reopened in January with discussion 
here and pydev.  Is more discussion needed?  Final votes on pydev?

-- 
Terry Jan Reedy