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<title>Logtalk built-in method: expand_term/2</title>
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<div class="top-left">Logtalk reference manual</div>
<div class="top-right">Built-in method: expand_term/2</div>
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<h2 class="code">expand_term/2</h2>
<h4>Description</h4>
<pre>expand_term(Term, Expansion)</pre>
<p>
Expands a term. The most common use is to expand a grammar rule into a clause. Users may override the default Logtalk grammar rule translator by defining clauses for the predicate <a href="term_expansion2.html"><code>term_expansion/2</code></a>.
<p>
</p>
The expansion works as follows: if the first argument is a variable, then it is unified with the second argument; if the first argument is not a variable and clauses for the <code>term_expansion/2</code> predicate are within scope, then this predicate is called to provide an expansion that is then unified with the second argument; if the <code>term_expansion/2</code> predicate is not used and the first argument is a compound term with functor <code>-->/2</code> then the default Logtalk grammar rule translator is used, with the resulting clause being unified with the second argument; when the translator is not used, the two arguments are unified.
</p>
<p>
This built-in method may be used to expand a grammar rule into a clause for use with the built-in database methods.
</p>
<h4>Template and modes</h4>
<pre>expand_term(?term, ?term)</pre>
<h4>Errors</h4>
<dl class="errors">
<dt>(none)</dt>
</dl>
<h4>Examples</h4>
<blockquote>
<dl>
<dt>(none)</dt>
</dl>
</blockquote>
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<span class="date">Last updated on: January 29, 2006</span>
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