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

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.. index:: pair: info/2; Directive
.. _directives_info_2:

``info/2``
==========

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

::

   info(Name/Arity, [Key is Value, ...])
   info(Name//Arity, [Key is Value, ...])

Documentation directive for predicates and grammar rule non-terminals.
The first argument is either a predicate indicator or a grammar rule
non-terminal indicator. The second argument is a list of pairs using the
format *Key is Value*. See the :ref:`documenting_predicate`
section for a description of the default keys.

Template and modes
------------------

::

   info(+predicate_indicator, +predicate_info_list)
   info(+non_terminal_indicator, +predicate_info_list)

Examples
--------

::

   :- info(empty/1, [
       comment is 'True if the argument is an empty list.',
       argnames is ['List']
   ]).
       
   :- info(sentence//0, [
       comment is 'Rewrites a sentence into a noun phrase and a verb phrase.'
   ]).

.. seealso::

   :ref:`directives_info_1`,
   :ref:`directives_mode_2`,
   :ref:`methods_predicate_property_2`
