[Python-3000] optional argument annotations

[Jim Jewett]

On 11/23/06, Guido van Rossum <guido at python.org> wrote:
> On 11/23/06, Tony Lownds <tony at pagedna.com> wrote:
> > I have a working optional argument syntax implementation, I'm hoping
> > to get some direction on
> > the implementation decisions so far.... please see below.

I would rather see it integrated into a Signature object (Brett had an
implementation), instead of showing up as two separate attributes.

> >  >>> f.func_returns
> > Traceback (most recent call last):
> >    File "<stdin>", line 1, in <module>
> > AttributeError: 'function' object has no attribute 'func_returns'

> I would prefer this to be None. Attributes that don't always exist are
> a pain to use.

I suspect he was trying to distinguish "returns None" from "Doesn't
say what it returns".  There is no good way to do this, but a separate
flag on a Signature object seems the least bad to me.

-jJ