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<h2><code><a class="back" title="Return to index" href="../index.html#extends_object2_3">extends_object/2-3</a></code></h2>
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<h4>Description</h4>

<blockquote>
<pre>
extends_object(Prototype, Parent)

extends_object(Prototype, Parent, Scope)
</pre>
<p>
	Enumerates, by backtracking, all pairs of objects such that the first one extends the second.
</p>
</blockquote>

<h4>Template and modes</h4>

<blockquote>
<pre>
extends_object(?object_identifier, ?object_identifier)

extends_object(?object_identifier, ?object_identifier, ?scope)
</pre>
</blockquote>

<h4>Errors</h4>

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

<h4>Examples</h4>

<blockquote>
<pre>
| ?- extends_object(Object, state_space).

| ?- extends_object(Object, list, public).
</pre>
</blockquote>

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Last updated on: August 6, 2002
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