unit-returns-value.scala:4: warning: a pure expression does nothing in statement position; you may be omitting necessary parentheses
    if (b) return 5
                  ^
unit-returns-value.scala:4: warning: enclosing method f has result type Unit: return value discarded
    if (b) return 5
           ^
error: No warnings can be incurred under -Xfatal-warnings.
two warnings found
one error found