Assign a range to a variable (Python)

Question

Whenever I try to assign a range to a variable like so:

Var1 = range(10, 50)

Then try to print the variable:

Var1 = range(1         


        

Answer 1

This is something that was changed in Python 3.0. You could recreate a similar function in Python 2.7 like so,

def range(low, high=None):
  if high == None:
    low, high = 0, low
  i = low
  while i < high:
    yield i
    i += 1

The benefit of this, is that the list doesn't have to be created before its used.

for i in range(1,999999):
  text = raw_input("{}: ".format(i))
  print "You said {}".format(text)

Which works like this:

1: something
You said something
2: something else
You said something else
3: another thing
You said another thing

In Python 3.X, if we never get to the end of our loop (999997 iterations), it will never calculate all of the items. In Python 2.7 it has to build the entire range initially. In some older Python implementations, this was very slow.