   <span class="keyword">const</span> <span class="identifier">string_type</span> <span class="special">&amp;</span> min_dt_str<span class="special">,</span> 
                <span class="keyword">const</span> <span class="identifier">string_type</span> <span class="special">&amp;</span> max_dt_str<span class="special">)</span><span class="special">;</span></pre>Replace special value strings. </li>
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<pre class="literallayout"><span class="keyword">bool</span> <a name="idp39173152-bb"></