[Python-Dev] Extended Function syntax

[Michael Hudson]

Just van Rossum <just@letterror.com> writes:

> Jim Fulton wrote:
> 
> > In particular:
> > 
> >    def name(arg, ...) [expr1, expr2, expr3]:
> >        ...body...
> > 
> > would be equivalent to (some variation on):
> > 
> >    def name(arg, ...):
> >      ...body...
> > 
> >    name=expr1(expr2(expr3(name)))
> 
> With Michael's patch (which indeed still works) it's actually 
> 
>     name = expr3(expr2(expr1(name)))

I can't remember if that was deliberate or accidental.  I think
deliberate.

> > I wonder if the same mechanism could be used in class statements.
> > If I had this, I might say what interface a class implements
> > with:
> > 
> >    class foo(spam, eggs) [implements(IFoo, IBar)]:
> >       body of class
> > 
> > or (wo parens):
> > 
> >    class foo [implements(IFoo, IBar)]:
> >       body of class
> 
> I don't know how Zope interfaces work, but I can imagine the following
> could be made to work as well:
> 
>    class foo(spam, eggs) [IFoo, IBar]:
>       body of class
> 
> I think this would be wonderful. Would someone be interested in
> extending Michael's patch to also cover the class statement?

Maybe even me :-)  It wasn't very hard.

 http://starship.python.net/crew/mwh/hacks/meth-syntax-sugar-2.diff

You still can't use lambdas in the filter list.  I thought I'd fixed
that ages ago, but it seems not.

Cheers,
M.

-- 
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