Why doesn't Python have static variables?

Question

There is a questions asking how to simulate static variables in python.

Also, on the web one can find many different solutions to create static variables. (Though I

Answer 1

For caching or memoization purposes, decorators can be used as an elegant and general solution.

Answer 2

One alternative to a class is a function attribute:

def foo(arg):
    if not hasattr(foo, 'cache'):
        foo.cache = get_data_dict()
    return foo.cache[arg]

While a class is probably cleaner, this technique can be useful and is nicer, in my opinion, then a global.

Answer 3

An ill-advised alternative:

You can also use the side-effects of the definition time evaluation of function defaults:

def func(initial=0, my_static=[])
  if not my_static:
    my_static.append(initial)

   my_static[0] += 1
  return my_static[0]

print func(0), func(0), func(0)

Its really ugly and easily subverted, but works. Using global would be cleaner than this, imo.