#!/usr/bin/python



import sys



class rlist(list):

    def __init__(self, ls=[]):

        list.__init__(self, ls)

        self.current = 0

    def next(self):

        if self.current < len(self):

            self.current += 1

        else:

            self.current = 0

        return self.current

    def __delitem__(self, i):

        list.__delitem__(self, i)

        if i < self.current:

            if self.current != 0:

                self.current -= 1

            else:

                # FIXME: Move backward on delete?

                self.current = len(self)

        elif i == self.current:

            # FIXME: point to next or previous? overflow?

            self.current == self.current





def main():

    b = rlist(range(10))

    print b

    print 'next', b.next()

    print 'next', b.next()

    print 'next', b.next()

    print 'item', b[b.current]

    print 'current:', b.current

    del b[2]

    print 'delete 2'

    print b

    print 'current:', b.current

    print 'item', b[b.current]

    print 'next', b.next()

    print 'item', b[b.current]

    print b

if __name__ == '__main__':

    main()

# vim:ts=8:sw=4:expandtab

class RList(list):

    def __init__(self, v = ()):

        list.__init__(self, v)

    def __iter__(self):

        return RListIter(self)



class RListIter:

    def __init__(self, l):

        self._list = l

        self._iter = list.__iter__(l)

    def next(self):

        while 1:

            try:

                return self._iter.next()

            except StopIteration:

                if len(self._list) == 0:

                    raise

                else:

                    self._iter = list.__iter__(self._list)

    def __iter__(self):

        return self



if __name__ == '__main__':

    l = RList((1,2,3))

    for x, y in zip(range(8), l):

        print x, y