ier">string_type</span> <span class="special">&amp;</span> st<span class="special">)</span> <span class="keyword">const</span><span class="special">;</span></pre>Number of variables. </li>
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<pre class="literallayout"><span class="keyword">void</span> <a name="idp51498384-bb"></a><span class="identifier">erase</span><span class="special">(</span><span class="keyword">const</span> <span class="identifier">string_type</span> <span class="special">&amp;</span> id<span class="special">)</spa