Re: [PLUG] python and global name space

[Dan Widyono <dan@widyono.net>]

> You have to declare num as global in the *function*, not in the outer
> scope.

>From Python Essential Reference, 2nd ed., p66:

"One peculiarity of namespaces is the manipulation of global variables from
within a function. ... When variables are assigned in a function, they're
always bound to the function's local namespace; ... To alter this behavior,
use the global statement. ... is necessary only when global variables will be
modified."

This includes e.g.

a = 42
def foo():
  print a
  a = 13
  print a
foo()

This will error, since "a = 13" says you expect a to be local within the
function, so even the first "print a" is referencing a local variable, which
is yet undefined.

Dan W.
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