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		<title>Logtalk predicate directive: mode/2</title>
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<h2><code>mode/2</code></h2>


<h4>Description</h4>

<blockquote>
<pre>mode(Mode, Number_of_solutions)</pre>
<p>
	Most predicates can be used with several instantiations modes. This directive enables the specification of each instantiation mode and the corresponding number of solutions/proofs.
</p>
</blockquote>

<h4>Template and modes</h4>

<blockquote>
<pre>mode(+predicate_mode_term, +number_of_solutions)</pre>
</blockquote>

<h4>Examples</h4>

<blockquote>
<pre>:- mode(append(-, -, +), zero_or_more).

:- mode(append(+list, +list, -list), zero_or_one).

:- mode(var(@term), zero_or_one).

:- mode(arg(-, -, +), error).</pre>
</blockquote>

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