error_fun_ret4.nit:17,5--8: Control error: Reached end of function (a 'return' with a value was expected).
-error_fun_ret4.nit:19,2--22,4: Warning: use 'loop' instead of 'while true do'.
+error_fun_ret4.nit:19,2--22,4: Warning: use `loop` instead of `while true do`.