Understanding closures

[Alex Martelli]

Ramashish Baranwal <ramashish.lists at gmail.com> wrote:

> Hi,
> 
> I want to use variables passed to a function in an inner defined
> function. Something like-
> 
> def fun1(method=None):
>     def fun2():
>         if not method: method = 'GET'
>         print '%s: this is fun2' % method
>         return
>     fun2()
> 
> fun1()
> 
> However I get this error-
> UnboundLocalError: local variable 'method' referenced before
> assignment
> 
> This however works fine.
> 
> def fun1(method=None):
>     if not method: method = 'GET'
>     def fun2():
>         print '%s: this is fun2' % method
>         return
>     fun2()
> 
> fun1()
> 
> Is there a simple way I can pass on the variables passed to the outer
> function to the inner one without having to use or refer them in the
> outer function?

Sure, just don't ASSIGN TO those names in the inner function.  Any name
ASSIGNED TO in a given function is local to that specific function (save
for global statements, which bypass variable of containing functions
anyway).


Alex