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<h1><span class="kind-constructor">MfmFn</span> constructor 
    <a href="https://dart.dev/null-safety" class="feature feature-null-safety" title="Supports the null safety language feature.">Null safety</a>
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      <span class="name ">MfmFn</span>(<wbr><ol class="parameter-list"><li><span class="parameter" id="-param-name">{<span>required</span> <span class="type-annotation"><a href="