Function creation (what happened?)

[Peter Otten]

Viktor wrote:

> Can somebody give me an explanation what happened here (or point me to
> some docs)?
> 
> Code:
> 
> HMMM = None
> 
> def w(fn):
>     print 'fn:', id(fn)
>     HMMM = fn
>     print 'HMMM:', id(HMMM)

This prints the id() of the local (to the function w()) HMMM variable

>     def wrapper(*v, **kw):
>         fn(*v, **kw)
>     wrapper.i = fn
>     print 'wrapper:', id(wrapper)
>     return wrapper
> 
> class A:
>     @w
>     def __init__(self): pass
> 
> print 'A.__init__:', id(A.__init__)
> print 'A.__init__.i:', id(A.__init__.i)
> print 'HMMM:', id(HMMM)

while this prints the id() of the global HMMM variable. Python assumes that
a variable is local to a function if there is an assignment to that
variable anywhere inside that function.

If you want to change the variable (Python-lingo "rebind the name") HMMM
declare it as global in the function:

def w(fn):
    global HMMM
    # ...
    HMMM = fn
    # ...

Otherwise I've no idea what you are trying to do here...

Peter