def __init__(self, meaning, glue, indices=None):
        if not indices:
            indices = set()

        if isinstance(meaning, str):
            self.meaning = drt.DrtParser().parse(meaning)
        elif isinstance(meaning, drt.AbstractDrs):
            self.meaning = meaning
        else:
            raise RuntimeError, 'Meaning term neither string or expression: %s, %s' % (meaning, meaning.__class__)