span> <span class="identifier">string_type</span> <a name="idp115412112-bb"></a><span class="identifier">transform</span><span class="special">(</span><span class="identifier">FwdIter</span> begin<span class="special">,</span> <span class="identifier">FwdIter</span> end<span class="special">)</span><span class="special">;</span></pre>
<p>Returns a sort key for the character sequence designated by the iterator range [F1, F2) such that if the character sequence [G1, G2) sorts before the character sequence [H1