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.. rst-class:: align-right

built-in predicate

.. index:: pair: object_property/2; Built-in predicate .. _predicates_object_property_2:

object_property/2

Description

::

object_property(Object, Property)

Enumerates, by backtracking, the properties associated with the defined objects. The valid properties are listed in the language grammar section on :ref:`entity properties <grammar_entity_properties>` and described in the User Manual section on :ref:`object properties <objects_properties>`.

Modes and number of proofs

::

object_property(?object_identifier, ?object_property) - zero_or_more

Errors

| Object is neither a variable nor a valid object identifier: | type_error(object_identifier, Object) | Property is neither a variable nor a callable term: | type_error(callable, Property) | Property is a callable term but not a valid object property: | domain_error(object_property, Property)

Examples

::

% enumerate the properties of the logtalk built-in object: | ?- object_property(logtalk, Property).

Property = context_switching_calls ; Property = source_data ; Property = threaded ; Property = static ; Property = built_in ; ...

.. seealso::

:ref:predicates_abolish_object_1, :ref:predicates_create_object_4, :ref:predicates_current_object_1, :ref:predicates_extends_object_2_3, :ref:predicates_instantiates_class_2_3, :ref:predicates_specializes_class_2_3, :ref:predicates_complements_object_2