Question

I currently have code like this:

cache = 1
def foo():
    global cache
    # many
    # lines
    # of code
    cache = 2

However, this may lead to hard-to-find-bugs in the future, because the reader may not notice that global cache appears somewhere above cache = 2. Alternatively, a contributor may mistakenly add def bar(): cache = 2 and forget to add the global cache.

How can I avoid this pitfall?

Answer 1

class Cache:
     myvar = 1

def foo():
    Cache.myvar = 2

This way, Cache.myvar is practically a “global”. It’s possible to read/write to it from anywhere.

I prefer this over the dictionary alternative, because it allows for auto-complete of the variable names.