+<p>A virtual method for the <a class="link" href="harfbuzz-hb-unicode.html#hb-unicode-funcs-t" title="hb_unicode_funcs_t"><span class="type">hb_unicode_funcs_t</span></a> structure.</p>
+<p>This method should compose a sequence of two input Unicode code
+points by canonical equivalence, returning the composed code
+point in a <a class="link" href="harfbuzz-hb-common.html#hb-codepoint-t" title="hb_codepoint_t"><span class="type">hb_codepoint_t</span></a> output parameter (if successful).
+The method must return an <a class="link" href="harfbuzz-hb-common.html#hb-bool-t" title="hb_bool_t"><span class="type">hb_bool_t</span></a> indicating the success
+of the composition.</p>
+<div class="refsect3">
+<a name="hb-unicode-compose-func-t.parameters"></a><h4>Parameters</h4>
+<div class="informaltable"><table class="informaltable" width="100%" border="0">
+<colgroup>
+<col width="150px" class="parameters_name">
+<col class="parameters_description">
+<col width="200px" class="parameters_annotations">
+</colgroup>
+<tbody>
+<tr>
+<td class="parameter_name"><p>ufuncs</p></td>
+<td class="parameter_description"><p>A Unicode-functions structure</p></td>
+<td class="parameter_annotations"> </td>
+</tr>
+<tr>
+<td class="parameter_name"><p>a</p></td>
+<td class="parameter_description"><p>The first code point to compose</p></td>
+<td class="parameter_annotations"> </td>
+</tr>
+<tr>
+<td class="parameter_name"><p>b</p></td>
+<td class="parameter_description"><p>The second code point to compose</p></td>
+<td class="parameter_annotations"> </td>
+</tr>
+<tr>
+<td class="parameter_name"><p>ab</p></td>
+<td class="parameter_description"><p>The composed code point. </p></td>
+<td class="parameter_annotations"><span class="annotation">[<acronym title="Parameter for returning results. Default is transfer full."><span class="acronym">out</span></acronym>]</span></td>
+</tr>
+<tr>
+<td class="parameter_name"><p>user_data</p></td>
+<td class="parameter_description"><p>user data pointer passed by the caller</p></td>
+<td class="parameter_annotations"> </td>
+</tr>
+</tbody>
+</table></div>
+</div>
+<div class="refsect3">
+<a name="hb-unicode-compose-func-t.returns"></a><h4>Returns</h4>
+<p> <code class="literal">true</code> is <em class="parameter"><code>a</code></em>
+,<em class="parameter"><code>b</code></em>
+composed, <code class="literal">false</code> otherwise</p>
+</div>