title: How to map single object of type x to array of object of type y using automapper
body: <pre><code>Mapper.CreateMap&lt;A, B&gt;()
        .ForMember(dest =&gt; dest.defs, opt =&gt; opt.MapFrom(origin =&gt; origin.abc));
  </code></pre>
  
  <p>where defs is array of Def (Def[])</p>
  
  <p>how to map?</p>