..
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   SPDX-FileCopyrightText: 1998-2026 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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.. rst-class:: align-right

**directive**

.. index:: pair: discontiguous/1; Directive
.. _directives_discontiguous_1:

``discontiguous/1``
===================

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

::

   discontiguous(Name/Arity)
   discontiguous((Name/Arity, ...))
   discontiguous([Name/Arity, ...])

   discontiguous(Entity::Name/Arity)
   discontiguous((Entity::Name/Arity, ...))
   discontiguous([Entity::Name/Arity, ...])

   discontiguous(Module:Name/Arity)
   discontiguous((Module:Name/Arity, ...))
   discontiguous([Module:Name/Arity, ...])

   discontiguous(Name//Arity)
   discontiguous((Name//Arity, ...))
   discontiguous([Name//Arity, ...])

   discontiguous(Entity::Name//Arity)
   discontiguous((Entity::Name//Arity, ...))
   discontiguous([Entity::Name//Arity, ...])

   discontiguous(Module:Name//Arity)
   discontiguous((Module:Name//Arity, ...))
   discontiguous([Module:Name//Arity, ...])

Declares :term:`discontiguous <discontiguous predicate>` predicates and
discontiguous grammar rule non-terminals. The use of this directive should
be avoided as not all :term:`backend Prolog compilers <backend Prolog compiler>`
support discontiguous predicates.

.. warning::

   Some backend Prolog compilers declare the atom ``discontiguous`` as
   an operator for a lighter syntax. But this makes the code non-portable
   and is therefore a practice best avoided.

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

::

   discontiguous(+predicate_indicator_term)
   discontiguous(+non_terminal_indicator_term)

Examples
--------

::

   :- discontiguous(counter/1).

   :- discontiguous((lives/2, works/2)).

   :- discontiguous([db/4, key/2, file/3]).
