on_llm_new_token() — langchain Function Reference

Source Code

libs/langchain/langchain_classic/callbacks/streaming_stdout_final_only.py lines 79–96

    def on_llm_new_token(self, token: str, **kwargs: Any) -> None:
        """Run on new LLM token. Only available when streaming is enabled."""
        # Remember the last n tokens, where n = len(answer_prefix_tokens)
        self.append_to_last_tokens(token)

        # Check if the last n tokens match the answer_prefix_tokens list ...
        if self.check_if_answer_reached():
            self.answer_reached = True
            if self.stream_prefix:
                for t in self.last_tokens:
                    sys.stdout.write(t)
                sys.stdout.flush()
            return

        # ... if yes, then print tokens from now on
        if self.answer_reached:
            sys.stdout.write(token)
            sys.stdout.flush()