..
   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

   Unless required by applicable law or agreed to in writing, software
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   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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.. rst-class:: align-right

**built-in method**

.. index:: pair: instantiation_error/0; Built-in method
.. _methods_instantiation_error_0:

``instantiation_error/0``
=========================

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

::

   instantiation_error

Throws an instantiation error. Used when an argument or one of its
sub-arguments is a variable but a non-variable term is required. For example,
trying to open a file with a variable for the input/output mode.

This built-in method is declared private and thus cannot be used as a message
to an object. Calling this predicate is equivalent to the following sequence
of calls:


::

   ...,
   context(Context),
   throw(error(instantiation_error, Context)).

This allows the user to generate errors in the same format used by the
runtime.

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

::

   instantiation_error - error

Errors
------

| When called:
|     ``instantiation_error``

Examples
--------

::

   ...,
   var(Handler),
   instantiation_error.

.. seealso::

   :ref:`methods_catch_3`,
   :ref:`methods_throw_1`,
   :ref:`methods_context_1`,
   :ref:`methods_uninstantiation_error_1`,
   :ref:`methods_type_error_2`,
   :ref:`methods_domain_error_2`,
   :ref:`methods_consistency_error_3`,
   :ref:`methods_existence_error_2`,
   :ref:`methods_permission_error_3`,
   :ref:`methods_representation_error_1`,
   :ref:`methods_evaluation_error_1`,
   :ref:`methods_resource_error_1`,
   :ref:`methods_syntax_error_1`,
   :ref:`methods_system_error_0`
