title: In scala, why doesn't list.flatMap(List) work?
body: <p>This works well</p>
  
  <pre><code>val l = List(1,2,3)
  l.flatMap(x =&gt; List(x))
  </code></pre>
  
  <p>But this doesn't work:</p>
  
  <pre><code>l.flatMap(List)
  </code></pre>
  
  <p>And this doesn't work either:</p>
  
  <pre><code>l.flatmap(List.apply _)
  </code></pre>
  
  <p>Does anyone have ideas about this? Thanks!</p>