title: Block is unfinished
body: <p>This code fragment is compiled:</p>
  
  <pre>
  let test =
      let x = 1
      printfn "%A" x
  </pre>
  
  <p>If the last line is removed, there is the following compilation error:</p>
  
  <pre>
  error FS0588: Block following this 'let' is unfinished. Expect an expression.
  </pre>
  
  <p>What does this message mean? In C#/C++ I would expect the "Unused variable" warning in such situation, but F# gives something different.</p>