span> <span class="identifier">value_type</span> <span class="special">&amp;</span> x<span class="special">)</span><span class="special">;</span></pre>Returns index and shift (if axis has grown) for the passed argument. </li>
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<pre class="literallayout"><span class="keyword">auto</span> <a name="idm14169-bb"></a><span class="identifier">value</span><span class="special">(</span><span class="identifier">index_type</span> idx<span class="special">)</span> <span class="keyword">const</span