title: The target type of this expression must be a functional interface in MethodReferences
body: <p>Why does the following code not compile.</p>
  
  <p><code>Consumer con = (s) -&gt; System.out::println;</code></p>
  
  <p>It says </p>
  
  <blockquote>
    <p>The target type of this expression must be a functional interface</p>
  </blockquote>
  
  <p>even though Consumer is a Functional Interface. The below works just fine.</p>
  
  <p><code>Consumer con2 = (s) -&gt; {System.out.println(s);};</code></p>