from bu4.evaluation.aftervalue import envtype, Evaluable


class LinkingState:
    pass


class Linked:
    future: set[bytes]

    def link(self) -> LinkingState:
        raise NotImplementedError

    def evaluable(self, env: envtype) -> Evaluable:
        raise NotImplementedError

    def unlink(self) -> 'Parsed':
        raise NotImplementedError

    def __bytes__(self):
        return bytes(self.unlink())


class Parsed:
    def link(self, promise: set[bytes]) -> Linked:
        raise NotImplementedError

    def __bytes__(self):
        raise NotImplementedError