[Python-Dev] Re: closure semantics
Guido van Rossum
guido at python.org
Thu Oct 23 23:40:52 EDT 2003
> Well, the listed variables are "global" to the current local scope.
> I find the rename argument a bit specious. If I rename a function I
> have to change all the references to it today. This is just one
> more. Since "global" is a declarative statement, the compiler can
> tell you immediately that it can't find the old function name.
Right, I tend to agree.
> Guido> I saw a variant where the syntax was
> Guido> 'global' vars 'in' 'def'
> Guido> which solves that concern (though not particularly elegantly).
> I don't see how that can work though. What does 'def' mean in this
> case? There can be multiple lexically enclosing functions, any of
> which have the same local variable x which you might want modify.
Yeah, but usually that's not a problem. The compiler knows about all
those x-es, and uses the innermost (nearest) one. This matches what
it does when *referencing* a non-local variable, which doesn't need a
--Guido van Rossum (home page: http://www.python.org/~guido/)
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