keyword"></span><span class="token keyword">fun </span><span class="token operator">&lt;</span><span class="token keyword"></span><a href="to-not-empty-set.html">E</a><span class="token operator">&gt; </span><a href="https://kotlinlang.org/api/latest/jvm/stdlib/kotlin.collections/-collection/index.html">Collection</a><span class="token operator">&lt;</span><span class="token keyword"></span><a href="to-not-empty-set.html">E</a><span class="token operator">&gt;</span><span class="token punctuation">.</span><