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<div class="top-left">Logtalk reference manual</div> 
<div class="top-right">Built-in predicate: instantiates_class/2-3</div>
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<h2 class="codenp">instantiates_class/2-3<span id="builtins_instantiates_class2_3"/></h2>


<h4>Description</h4>

<pre>instantiates_class(Instance, Class)

instantiates_class(Instance, Class, Scope)</pre>
<p>
Enumerates, by backtracking, all pairs of objects such that the first one instantiates the second. The relation scope is represented by the atoms <code>public</code>, <code>protected</code>, and <code>private</code>.
</p>

<h4>Template and modes</h4>

<pre>instantiates_class(?object_identifier, ?object_identifier)

instantiates_class(?object_identifier, ?object_identifier, ?scope)</pre>

<h4>Errors</h4>

<dl>
	<dt>Instance is neither a variable nor a valid object identifier:</dt>
		<dd><code>type_error(object_identifier, Instance)</code></dd>
	<dt>Class is neither a variable nor a valid object identifier:</dt>
		<dd><code>type_error(object_identifier, Class)</code></dd>
	<dt>Scope is neither a variable nor a valid entity scope:</dt>
		<dd><code>type_error(scope, Scope)</code></dd>
</dl>

<h4>Examples</h4>

<pre>| ?- instantiates_class(water_jug, state_space).

| ?- instantiates_class(Space, state_space, public).</pre>

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