[Types-sig] RE: [meta-sig] The Types-SIG is comatose. Let's retire it.

[Jeremy Hylton]

Paul Prescod proposes a new charter for the types-sig:
> * the goal is a optional static type system for version 2. 
> * presume that the type/class dichotomy has been removed in V2
> * backwards compatibility with current code is relatively important
> * compatibility with the Python 1.x interpreter is NOT important
> * interfaces are not an issue
> * parameterized (template) types are not available
> * names are type checked, not expressions
> * got now, only named types (types and classes) can be declared, not
>lists and tuples of types

If you're going to develop a static type system to describe Python
programs (optional or otherwise), then I think you can't punt on all
the things you want to punt on.

> * interfaces are not an issue
Yes, they are :-).

> * parameterized (template) types are not available
They need to be.

> * names are type checked, not expressions
Expressions need type checking, too!  I'm thinking of the "the"
special form in Common Lisp.  (I don't have much experience with CL,
so I'd appreciate input from someone who is.)

Regardless of these minor quibbles, my largest complaint is:
> * the goal is a optional static type system for version 2. 

What exactly is the deliverable.  Saying an "optional static type
system" is a bit vague.  What is it specifically?  A formal
specification of the type system?  A stand-alone utility that reports
type errors?  A new compiler?

If this is a type system for Python 2, it seems that the best a SIG
can hope for right now is a specification of the type system.  Since
Py2 design hasn't even started.

Jeremy