title: What does this error message " Unexpected do block in function application" mean?
body: <p>I'm trying to compile this function but I get an error. What is it that Haskell is not happy about?</p>
  
  <pre><code>copyFile :: FilePath -&gt;  FilePath -&gt; IO()
  copyFile fromFile toFile = 
       do c &lt;- readFile fromFile
      writeFile toFile c 
  </code></pre>
  
  <p>Unexpected do block in function application:
          do c &lt;- readFile fromFile
      You could write it with parentheses
      Or perhaps you meant to enable BlockArguments?</p>