Late variable binding in python

gistfile1.py

#!/usr/bin/env python
# encoding: utf-8

"""Testing late binding of variables."""

# last value of j is used everywhere

bars = [lambda i: j * i for j in range(5)]
assert all(b(1) == 4 for b in bars), "for lambda functions"

bazs = []
for j in range(5):
  def baz(i):
    return i * j
  bazs.append(baz)
assert all(b(1) == 4 for b in bazs), "and normal functions"

# not here since j is passed by value to foo

def foo(j):
  def _foo(i):
    return j * i
  return _foo
foos = [foo(j) for j in range(5)]
assert not all(b(1) == 4 for b in foos), "but not here"