!= package:leancheck

Equality == lifted over errorToLeft

> 1 `div` 1  !==!  2 `div` 2
True

> 1 `div` 1  !==!  1 `div` 2
False

> 1 `div` 1  !==!  1 `div` 0
False

> 6 `mod` 0  !==!  2 `div` 0
True

> head []  !==!  tail []
False

> error "a"  !==!  error "a"
True

> error "a"  !==!  error "b"
False

On error, this function returns the result of comparing the first line of error values.