span>    <span class="comment">// usage:</span></div>
<div class="line"><a id="l00128" name="l00128"></a><span class="lineno">  128</span>    <span class="comment">//  on(stream)</span></div>
<div class="line"><a id="l00129" name="l00129"></a><span class="lineno">  129</span>    <span class="comment">//      .when(event)</span></div>
<div class="line"><a id="l00130" name="l00130"></a><span class="lineno">  130</span>    <span class="comment">//      .next&lt;launch&gt;(1,1).apply(...)</span></div>
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