def process_next_expression(self, context):
        try:
            tok = self.token()
        except ExpectedMoreTokensException:
            raise ExpectedMoreTokensException(self._currentIndex+1, message='Expression expected.')

        accum = self.handle(tok, context)

        if not accum:
            raise UnexpectedTokenException(self._currentIndex, tok, message='Expression expected.')

        return self.attempt_adjuncts(accum, context)
Parse the next complete expression from the stream and return it.
dataset/ETHPy150Open nltk/nltk/nltk/sem/logic.py/LogicParser.process_next_expression