AnonymousFox

//usr/lib64/python2.7/site-packages/mx/Stack/UserStack.py

""" A pure Python Stack implementation modelled after mxStack.

Copyright (c) 2000, Marc-Andre Lemburg; mailto:mal@lemburg.com
    Copyright (c) 2000-2011, eGenix.com Software GmbH; mailto:info@egenix.com
    See the documentation for further information on copyrights,
    or contact the author. All Rights Reserved.
"""

class UserStack:

def __init__(self):

self.stack = ()

def push(self,x):

self.stack = (x,self.stack)

def pop(self):

x, self.stack = self.stack
        return x

def not_empty(self):

return len(self.stack) != 0

def top(self):

return self.stack[0]

def __len__(self):

i = 0
        s = self.stack
        while len(s) != 0:
            s = s[1]
            i = i + 1
        return i

def __repr__(self):

l = []
        s = self.stack
        while len(s) != 0:
            l.append(repr(s[0]))
            s = s[1]
        return '<UserStack [%s]>' % ', '.join(l)

def __str__(self):

l = []
        s = self.stack
        while len(s) != 0:
            l.append(s[0])
            s = s[1]
        return 's' + repr(l)