Kevin Jacobs <[EMAIL PROTECTED]> wrote:
> Why not extend the interface to the locals builtin and add a __getitem__
> that returns a proxy to access locals defined in other lexical scopes
> via __{get/set/del}attr_:
>
> def counter(num):
> num = 1
> def inc():
> locals[1].num += 1
> return outer.num
> return inc
>
> Where, for CPython, locals[n] gives access to
> NamespaceProxy(sys._getframe(n).f_locals).
Two nits: First, I suspect that you meant to write "return
locals[1].num". Second, sys._getframe doesn't do what you want, here.
It reaches back up the call chain, not out into lexically containing scopes.
That said, I like the idea of giving "locals[]" the meaning you
intended. It has the advantage of not adding any new keywords or
syntactic constructs, but the disadvantage of not explicitly signaling
that locals in a given scope will be twiddled elsewhere. Also, for
efficiency's sake, it might be desirable to only allow a literal integer
as the index, and to deal with use of "locals[]" at compile time rather
than dynamically. I'm not sure how much overhead would be involved in
enabling dynamic lookup of arbitrary lexically containing scopes, but I
would *not* want to enable stuff like "locals[i * 2 - 1]".
Cheers,
Evan @ 4-am
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