s="extype">Double</span></span>)</span><span class="result">: <a href="ProbabilityDistribution$$MixinOpt.html" name="provingground.ProbabilityDistribution.MixinOpt" id="provingground.ProbabilityDistribution.MixinOpt" class="extype">MixinOpt</a>[<span name="provingground.ProbabilityDistribution.Mixture.A" class="extype">A</span>]</span></span><p class="shortcomment cmt">generates from the mixed in optional valued distribution with probability <code>weight</code>,
otherwise, or if the optional returns None, d