Binding frustration

[JCM]

Rob Hunter <rob at cs.brown.edu> wrote:
...

> def getGenres(title):  #it takes a movie title and returns a list of 
> genres that the movie falls into

>      result = [] # my accumulator

>      def inGenre(g): # g is a genre
>          if <here I test if "title" is of genre g (using a simple Python 
> dictionary I have collected from a mini web crawl)>:
>                result = result + [g] # if title is of genre g, then add 

Here you're attempting to rebind a variable which lives in an
enclosing scope.  This isn't possible in Python (except for globals).
Use result.append(g) instead and it should work.