elseifDoErrorPos.lean:4:10-4:11: error: Application type mismatch: In the application
  @ite ?m x
the argument
  x
has type
  Nat
but is expected to have type
  Prop
elseifDoErrorPos.lean:7:11-7:14: error: Application type mismatch: In the application
  pure "a"
the argument
  "a"
has type
  String
but is expected to have type
  Nat