..
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   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: phrase//1; Built-in method
.. _methods_phrase_1:

``phrase//1``
=============

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

::

   phrase(NonTerminal)

This non-terminal takes a non-terminal or a grammar rule body and parses
it using the implicit difference list of tokens. A common use is to wrap
what otherwise would be a naked variable in a grammar rule body.

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

::

   phrase(+callable) - zero_or_more

Errors
------

| ``NonTerminal`` is a variable:
|     ``instantiation_error``
| ``NonTerminal`` is neither a variable nor a callable term:
|     ``type_error(callable, NonTerminal)``

Examples
--------

   (none)

.. seealso::

   :ref:`methods_call_1`,
   :ref:`methods_phrase_2`,
   :ref:`methods_phrase_3`
