Resolve tail recursion depth limitation in python

run.py

"""
Thanks to Kyle Miller for his article "Tail call recursion in Python" [1].

Despite how good is to remove this limitation, probably, you have to be
aware of why this feature is not officially supported. [2]
   
[1]: http://www.kylem.net/programming/tailcall.html
[2]: http://neopythonic.blogspot.com/2009/04/tail-recursion-elimination.html
"""

class TailCall(object):
    def __init__(self, __function__):
        self.__function__ = __function__
        self.args = None
        self.kwargs = None
        self.has_params = False

    def __call__(self, *args, **kwargs):
        self.args = args
        self.kwargs = kwargs
        self.has_params = True
        return self

    def __handle__(self):
        if not self.has_params:
            raise TypeError
        if type(self.__function__) is TailCaller:
            return self.__function__.call(*self.args, **self.kwargs)
        return self.__function__(*self.args, **self.kwargs)


class TailCaller(object):
    def __init__(self, call):
        self.call = call

    def __call__(self, *args, **kwargs):
        ret = self.call(*args, **kwargs)
        while type(ret) is TailCall:
            ret = ret.__handle__()
        return ret


@TailCaller
def factorial(n, prev=1):
    if n < 2:
        return prev
    return TailCall(factorial)(n-1, n * prev)