.. This file is part of Logtalk https://logtalk.org/ SPDX-FileCopyrightText: 1998-2024 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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.. rst-class:: align-right

built-in method

.. index:: pair: ask_question/5; Built-in method .. _methods_ask_question_5:

ask_question/5

Description

::

ask_question(Kind, Component, Question, Check, Answer)

Built-in method for asking a question represented by a term, Question, which is converted to the question text using the :ref:`logtalk::message_tokens(Question, Component) <methods_message_tokens_2>` hook predicate. This method is declared in the logtalk built-in object as a public predicate. The default question prompt and the input stream used for each Kind-Component pair can be found using the :ref:`logtalk::question_prompt_stream(Kind, Component, Prompt, Stream) <methods_question_prompt_stream_4>` hook predicate. The Check argument is a :term:closure that is converted into a checking goal by extending it with the user supplied answer. This predicate implements a read-loop that terminates when the checking predicate succeeds.

This predicate starts by calling the :ref:`logtalk::question_hook(Question, Kind, Component, Tokens, Check, Answer) <methods_question_hook_6>` hook predicate. If this predicate succeeds, the ask_question/5 predicate assumes that the question have been successfully asked and replied.

Modes and number of proofs

::

ask_question(+nonvar, +nonvar, +nonvar, +callable, -term) - one

Meta-predicate template

::

ask_question(*, *, *, 1, *)

Errors

(none)

Examples

::

..., logtalk::ask_question(enter_age, question, my_app, integer, Age), ...

.. seealso::

:ref:methods_question_hook_6, :ref:methods_question_prompt_stream_4, :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_print_message_token_4