On Sat, 20 Feb 2010 17:34:15 -0800, Jonathan Gardner wrote: > In terms of "global", you should only really use "global" when you are > need to assign to a lexically scoped variable that is shared among other > functions. For instance: > > def foo(): > i = 0 > def inc(): global i; i+=1 > def dec(): global i; i-=1 > def get(): return i > return (inc, dec, get)
That doesn't do what you think it does: >>> def foo(): ... i = 0 ... def inc(): global i; i+=1 ... def dec(): global i; i-=1 ... def get(): return i ... return (inc, dec, get) ... >>> inc = foo()[0] >>> inc() Traceback (most recent call last): File "<stdin>", line 1, in <module> File "<stdin>", line 3, in inc NameError: global name 'i' is not defined The problem is that i is not global. Inside the inc and dec functions, you need to declare i nonlocal, not global, and that only works in Python 3 or better. -- Steven -- http://mail.python.org/mailman/listinfo/python-list
