[Types-sig] Type Annotations Progress report

[Tim Peters]

[Paul Prescod]
> Before I documented everything I wanted to do a real-world test. So I
> added type annotations to the os module. I even added a new type that
> was local to that module for handling P_WAIT, P_NOWAIT. I'd appreciate
> if people would at least take a cursory peek at the os module, if not
> the implementation.
>
> OS: www.prescod.net/pytypes/os.py
> Implementation: http://www.prescod.net/pytypes/typecheck.py

Paul, you know the rule:  each time this SIG reincarnates, the first msg
announcing an actual implementation kills it again <0.7 wink>.

> ...
> Remember that this is experimental, transitional, prototype, type
> annotation system. The syntax is not ideal. Nevertheless, I think it is
> quite simple, easy to use and immediately useful.

Yup!

Note that there are several misdeclarations, such as:

def execl(file, *args):
    """execl(file, *args)

    Execute the executable file with argument list args, replacing the
    current process. """
    __types__= {"file: Old directory name": IString,
                    "args: New directory name": IString}
    __paramcheck__()
    execv(file, args)

args should be a tuple of IStrings, right?

mostly-a-type-system-exists-to-help-programmers-debug-type-
    declarations<wink>-ly y'rs  - tim