Loop Labels - Python hack for breaking out of nested loops.

loop_label.py

class LoopLabel(object):
    def __init__(self):
        super(LoopLabel, self).__init__()

        class MyLoopLabel(Exception): pass
        self._label_exception = MyLoopLabel

    def __enter__(self):
        return self._label_exception

    def __exit__(self, exc_type, exc_val, exc_tb):
        if exc_type is self._label_exception:
            return True

        return False
        

# And usage:
with LoopLabel() as loop1:
    for x in range(10):
        print "x", x
        for y in range(10):
            print "y", y
            if x > 2:
                raise loop1()
            if y > 2:
                break