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def xlrange(start,stop=None,step=1):
    """xlrange([start=0,]stop[,step=1]) --> iterator object like xrange for longs"""
    if stop==None:
        stop=start
        start=0
    if step>0:
        while start<stop:
            yield start
            start+=step
    elif step<0:
        while start>stop:
            yield start
            start+=step
    else:
        raise ValueError, "xlrange() arg 3 (step) must not be zero"

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class xlrange:
    """xlrange([start=0,]stop[,step=1]) --> iterator object like xrange for longs"""
    def __init__(self,start,stop=None,step=1):
        if stop==None:
            stop=start
            start=0
        self.start,self.stop,self.step=start,stop,step
        if step>0:
            self.is_next=lambda :self.start<self.stop
        elif step<0:
            self.is_next=lambda :self.start>self.stop
        else:
            raise ValueError, "xlrange() arg 3 (step) must not be zero"
    def __iter__(self):
        return self
    def next(self):
        if self.is_next():
            i=self.start
            self.start+=self.step
            return i
        else:
            raise StopIteration

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start = 10000000000000
stop = 10000000100000
rstop = stop-start
for i in (start+x for x in xrange(0,rstop)):
    pass

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#!/usr/bin/env python2.4
# -*- coding: UTF-8 -*-
"""
    Modul:          xlrange_test
    Description:    Benchmark for xlrange
    Version:        0.1
    Copyright:      2004 by Milan & Dookie (Pythonforum)
    Created:        15. Dez. 2004
    Last modified:  16. Dez. 2004
    License:        free
    Requirements:   Python2.4
    Exports:        Classes and Functions to export
"""

def xlrange1(start,stop=None,step=1):
    """xlrange1([start=0,]stop[,step=1]) --> iterator object like xrange for longs"""
    if stop==None:
        stop=start
        start=0
    if step>0:
        while start<stop:
            yield start
            start+=step
    elif step<0:
        while start>stop:
            yield start
            start+=step
    else:
        raise ValueError, "xlrange() arg 3 (step) must not be zero"
        
def handleargs(arglist):
    """Take list of arguments and extract/create proper start, stop, and step
    values and return in a tuple found in Demos/"""
    try:
        if len(arglist) == 1:
            return 0, arglist[0], 1
        elif len(arglist) == 2:
            return arglist[0], arglist[1], 1
        elif len(arglist) == 3:
            if arglist[2] == 0:
                raise ValueError("xlrange() step argument must not be zero")
            return tuple([x for x in arglist])
        else:
            raise TypeError("xlrange() accepts 1-3 arguments, given", len(arglist))
    except TypeError:
        raise TypeError("xlrange() arguments must be numbers or strings "
        "representing numbers")

def xlrange2(*a):
    """xlrange2([start=0,]stop[,step=1]) --> iterator object like xrange for longs"""
    start, stop, step = tuple(long(x) for x in handleargs(a))
    value = start
    if step < 0:
        while value > stop:
            yield start
            value += step
    elif step > 0:
        while value < stop:
            yield start
            value += step

def xlrange3(*a):
    import sys
    start, stop, step = tuple(long(x) for x in handleargs(a))
    if step < 0:
        if start - stop > sys.maxint:
            return xlrange2(*a)
        elif abs(start) > sys.maxint or abs(stop) > sys.maxint:
            rstop = stop - start
            return (start + x for x in xrange(0, rstop, step))
    else:
        if stop - start > sys.maxint:
            return xlrange2(*a)
        elif abs(start) > sys.maxint or abs(stop) > sys.maxint:
            rstop = stop - start
            return (start + x for x in xrange(0, rstop, step))
    return xrange(*a)
    
if __name__ == "__main__":
    from timeit import Timer
    
    start = 10000000000
    r = 100000
    stop = start+r
    try:
        t = Timer("for i in xrange(%i, %i): pass" % (start, stop))
        print "%7.3f xrange(%i, %i)" % (t.timeit(10000000/r), start, stop)
    except OverflowError:
        pass
    t = Timer("for i in xlrange1(%i, %i): pass" % (start, stop),
              "from __main__ import xlrange1")
    print "%7.3f xlrange1(%i, %i)" % (t.timeit(10000000/r), start, stop)
    t = Timer("for i in xlrange2(%i, %i): pass" % (start, stop),
              "from __main__ import xlrange2")
    print "%7.3f xlrange2(%i, %i)" % (t.timeit(10000000/r), start, stop)
    t = Timer("for i in xlrange3(%i, %i): pass" % (start, stop),
              "from __main__ import xlrange3")
    print "%7.3f xlrange3(%i, %i)" % (t.timeit(10000000/r), start, stop)