How to add type annotation in let binding

Question

I\'m a beginner(ish) in Haskell and I find error message really hard to understand (I guess it comes with time). Anyway, to help me understanding my mistakes, I tried to add int

Answer 1

For anyone who is looking to type annotate the binding instead of the expression - ScopedTypeVariables allows you to do that too!

f1 = do
  let x :: Int = 5
  y :: Int <- someMonadicOperation
  return $ x + y