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<title>The @code{try} Statement - Untitled</title>
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<h3 class="section">10.9 The <code>try</code> Statement</h3>
<p><a name="index-g_t_0040code_007btry_007d-statement-578"></a><a name="index-g_t_0040code_007bcatch_007d-579"></a><a name="index-g_t_0040code_007bend_005ftry_005fcatch_007d-580"></a>
In addition to unwind_protect, Octave supports another limited form of
exception handling.
<p>The general form of a <code>try</code> block looks like this:
<pre class="example"> try
<var>body</var>
catch
<var>cleanup</var>
end_try_catch
</pre>
<p class="noindent">where <var>body</var> and <var>cleanup</var> are both optional and may contain any
Octave expressions or commands. The statements in <var>cleanup</var> are
only executed if an error occurs in <var>body</var>.
<p>No warnings or error messages are printed while <var>body</var> is
executing. If an error does occur during the execution of <var>body</var>,
<var>cleanup</var> can use the function <code>lasterr</code> to access the text
of the message that would have been printed. This is the same
as <code>eval (</code><var>try</var><code>, </code><var>catch</var><code>)</code> but it is more efficient since
the commands do not need to be parsed each time the <var>try</var> and
<var>catch</var> statements are evaluated. See <a href="Errors-and-Warnings.html#Errors-and-Warnings">Errors and Warnings</a>, for more
information about the <code>lasterr</code> function.
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