@property
    def either(self):
        """Transform pattern into an equivalent, with only top-level Either."""
        # Currently the pattern will not be equivalent, but more "narrow",
        # although good enough to reason about list arguments.
        ret = []
        groups = [[self]]
        while groups:
            children = groups.pop(0)
            types = [type(c) for c in children]
            if Either in types:
                either = [c for c in children if type(c) is Either][0]
                children.pop(children.index(either))
                for c in either.children:
                    groups.append([c] + children)
            elif Required in types:
                required = [c for c in children if type(c) is Required][0]
                children.pop(children.index(required))
                groups.append(list(required.children) + children)
            elif Optional in types:
                optional = [c for c in children if type(c) is Optional][0]
                children.pop(children.index(optional))
                groups.append(list(optional.children) + children)
            elif AnyOptions in types:
                optional = [c for c in children if type(c) is AnyOptions][0]
                children.pop(children.index(optional))
                groups.append(list(optional.children) + children)
            elif OneOrMore in types:
                oneormore = [c for c in children if type(c) is OneOrMore][0]
                children.pop(children.index(oneormore))
                groups.append(list(oneormore.children) * 2 + children)
            else:
                ret.append(children)
        return Either(*[Required(*e) for e in ret])
dataset/ETHPy150Open benoitc/gaffer/gaffer/docopt.py/Pattern.either/original