nt-class.html">int</a></span> <span class="parameter-name">hashCode</span>(<span class="parameter" id="hashCode-param-e"><span class="type-annotation">E</span> <span class="parameter-name">e</span></span>), </span> <span class="parameter" id="-param-isValidKey"><span class="type-annotation"><a href="dart-core/bool-class.html">bool</a></span> <span class="parameter-name">isValidKey</span>(<span class="parameter" id="isValidKey-param-potentialKey"><span class="type-annotation">dynamic</span> <span class="para