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<h3 class="section" id="The-try-Statement-1"><span>10.9 The try Statement<a class="copiable-link" href="#The-try-Statement-1"> ¶</a></span></h3>
<a class="index-entry-id" id="index-try-statement"></a>
<a class="index-entry-id" id="index-catch"></a>
<a class="index-entry-id" id="index-end_005ftry_005fcatch"></a>
<p>The original form of a <code class="code">try</code> block looks like this:
</p>
<div class="example">
<div class="group"><pre class="example-preformatted">try
<var class="var">body</var>
catch
<var class="var">cleanup</var>
end_try_catch
</pre></div></div>
<p>where <var class="var">body</var> and <var class="var">cleanup</var> are both optional and may contain any
Octave expressions or commands. The statements in <var class="var">cleanup</var> are
only executed if an error occurs in <var class="var">body</var>.
</p>
<p>No warnings or error messages are printed while <var class="var">body</var> is executing.
If an error does occur during the execution of <var class="var">body</var>, <var class="var">cleanup</var>
can use the functions <code class="code">lasterr</code> or <code class="code">lasterror</code> to access the
text of the message that would have been printed, as well as its
identifier. The alternative form,
</p>
<div class="example">
<div class="group"><pre class="example-preformatted">try
<var class="var">body</var>
catch <var class="var">err</var>
<var class="var">cleanup</var>
end_try_catch
</pre></div></div>
<p>will automatically store the output of <code class="code">lasterror</code> in the structure
<var class="var">err</var>. See <a class="xref" href="Errors-and-Warnings.html">Errors and Warnings</a>, for more information about the
<code class="code">lasterr</code> and <code class="code">lasterror</code> functions.
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