..
   This file is part of Logtalk <https://logtalk.org/>  
   Copyright 1998-2021 Paulo Moura <pmoura@logtalk.org>
   SPDX-License-Identifier: Apache-2.0

   Licensed under the Apache License, Version 2.0 (the "License");
   you may not use this file except in compliance with the License.
   You may obtain a copy of the License at

       http://www.apache.org/licenses/LICENSE-2.0

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   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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.. index:: pair: print_message_token/4; Built-in method
.. _methods_print_message_token_4:

``print_message_token/4``
=========================

Description
-----------

::

   print_message_token(Stream, Prefix, Token, Tokens)

User-defined hook method for printing a message token, declared in the
:ref:`logtalk <apis:logtalk/0>` built-in object as a public, multifile,
and dynamic predicate. It allows the user to intercept the printing of
a message token. This hook method is automatically called by the
:ref:`methods_print_message_tokens_3` built-in
method for each token.

Modes and number of proofs
--------------------------

::

   print_message_token(@stream_or_alias, @atom, @nonvar, @list(nonvar)) - zero_or_one

Errors
------

(none)

Examples
--------

::

   :- multifile(logtalk::print_message_token/4).
   :- dynamic(logtalk::print_message_token/4).

   % ignore all flush tokens
   logtalk::print_message_token(_Stream, _Prefix, flush, _Tokens).

.. seealso::

   :ref:`methods_message_hook_4`,
   :ref:`methods_message_prefix_stream_4`,
   :ref:`methods_message_tokens_2`,
   :ref:`methods_print_message_3`,
   :ref:`methods_print_message_tokens_3`,
   :ref:`methods_ask_question_5`,
   :ref:`methods_question_hook_6`,
   :ref:`methods_question_prompt_stream_4`
