..
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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: abolish/1; Built-in method
.. _methods_abolish_1:

``abolish/1``
=============

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

::

   abolish(Predicate)

Abolishes a runtime declared object dynamic predicate or an object local
dynamic predicate. Only predicates that are dynamically declared at runtime
(using a call to the :ref:`methods_asserta_1` or :ref:`methods_assertz_1`
built-in methods) can be abolished. 

When the predicate indicator is declared in a :ref:`directives_uses_2`
or :ref:`directives_use_module_2` directive, the predicate is abolished in
the referenced object or module. When the backend Prolog compiler supports
a module system, the predicate argument can also be module qualified.

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

::

   abolish(@predicate_indicator) - one

Errors
------

| ``Predicate`` is a variable:
|     ``instantiation_error``
| ``Functor`` is a variable:
|     ``instantiation_error``
| ``Arity`` is a variable:
|     ``instantiation_error``
| ``Predicate`` is neither a variable nor a valid predicate indicator:
|     ``type_error(predicate_indicator, Predicate)``
| ``Functor`` is neither a variable nor an atom:
|     ``type_error(atom, Functor)``
| ``Arity`` is neither a variable nor an integer:
|     ``type_error(integer, Arity)``
| ``Predicate`` is statically declared:
|     ``permission_error(modify, predicate_declaration, Name/Arity)``
| ``Predicate`` is a private predicate:
|     ``permission_error(modify, private_predicate, Name/Arity)``
| ``Predicate`` is a protected predicate:
|     ``permission_error(modify, protected_predicate, Name/Arity)``
| ``Predicate`` is a static predicate:
|     ``permission_error(modify, static_predicate, Name/Arity)``
| ``Predicate`` is not declared for the object receiving the message:
|     ``existence_error(predicate_declaration, Name/Arity)``

Examples
--------

| To abolish a local dynamic predicate or a dynamic predicate in :term:`this`:
|     ``abolish(Predicate)``
| To abolish a public or protected dynamic predicate in :term:`self`:
|     ``::abolish(Predicate)``
| To abolish a public dynamic predicate in an explicit object:
|     ``Object::abolish(Predicate)``

.. seealso::

   :ref:`methods_asserta_1`,
   :ref:`methods_assertz_1`,
   :ref:`methods_clause_2`,
   :ref:`methods_retract_1`,
   :ref:`methods_retractall_1`
   :ref:`directives_dynamic_0`,
   :ref:`directives_dynamic_1`,
   :ref:`directives_uses_2`,
   :ref:`directives_use_module_2`
