[Python-Dev] 2.5 and beyond (original) (raw)

Phillip J. Eby pje at telecommunity.com
Sat Jul 1 01:09:41 CEST 2006

At 07:04 PM 6/30/2006 -0400, Andrew Koenig wrote:

However, if I write

def g(): return x x = 42 g() the result is 42. With lexical scoping, I believe it should be undefined. The reason is that when the compiler encounters the definition of g, variable x is not yet bound, and there is nothing in the body of g that would bind it. Therefore, g requires a binding to exist at the time it is compiled; because no such binding exists, this example would be an error (at compile time) under lexical scoping.

That sounds like a bug, not a feature. It's frequently useful to have forward references in function bodies to names that are not yet globally bound, e.g. for classes, or mutually-recursive functions.

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