title: Trying to use a function in Data.Map.hs but it says not in scope ... Is it because of #if defined(TESTING)
body: <p>In <a href="http://hackage.haskell.org/packages/archive/containers/latest/doc/html/src/Data-Map.html" rel="nofollow">Data.Map</a> there are some functions like merge, glue, that I want to use but the compiler says they're not in scope. I notice at the top they are listed here:</p>
  
  <pre><code>#if defined(TESTING)
              -- * Internals
              , bin
              , balanced
              , join
              , merge
  #endif
  </code></pre>
  
  <p>I think this means I can't use them directly unless I've somehow defined TESTING but I've no clue how to do that and where. Please answer as if I'm retarded; don't assume I know you mean to type something in the command line instead of typing it in the program. </p>
  
  <p>I'm on Windows XP and using GHCi if it matters.</p>