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              <img src="../content/img/github.png" class="normal" />
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          <p>Defines a soft dependency. x must run before y, if it is present, but y does not require x to be run.</p>



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          <code onmouseout="hideTip(event, '5', 5)" onmouseover="showTip(event, '5', 5)">
            ( &lt;=&gt; ) x y
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