title: Functions in F# Discriminated Unions
body: <p>Is there a way to use functions in Discriminated Unions?  I am looking to do something like this:</p>
  
  <p><code>
  Type Test&lt;'a> = Test of 'a-> bool
  </code></p>
  
  <p>I know this is possible in Haskell using newtype and I was wondering what the equivalent in F# would be.</p>
  
  <p>Thanks.</p>