title: Does F# has a function to tell if a list contains a specific value?
body: <p>Haskell has "elem" predicate to tell like:</p>
  
  <pre><code>Prelude&gt; 5 `elem` [2,4..10]
  False
  </code></pre>
  
  <p>In F#, how to conveniently tell whether a value is in a list, or array, or seq or map, or dictionary?</p>