Calling ``xrange(10, 100, step=10)`` results in a
xrange(10, 100) iterator silently.  In contrast,
``range(10, 100, step=10)`` raises an exception.  See
test program below.

Two possible fixes:
1. fix xrange() so that it returns a xrange(10, 100,
10) iterator
2. make sure that xrange() raises an exception too.



#!/usr/bin/env python

def foo( min_, max_, step=1 ):
    print min_, max_, step

print '===================='
foo(10, 100, 10)
foo(10, 100, step=10)

print '===================='
print xrange(10, 100, 10)
print xrange(10, 100, step=10)

print '===================='
print range(10, 100, 10)
print range(10, 100, step=10)





elbow:/usr/.../lib/python2.4$ /tmp/a.py
====================
10 100 10
10 100 10
====================
xrange(10, 100, 10)
xrange(10, 100)
====================
[10, 20, 30, 40, 50, 60, 70, 80, 90]
Traceback (most recent call last):
  File "/tmp/a.py", line 16, in ?
    print range(10, 100, step=10)
TypeError: range() takes no keyword arguments

> /tmp/a.py(16)?()
-> print range(10, 100, step=10)
(Pdb) 
elbow:/usr/.../lib/python2.4$