import logic constant f : num → num constant g : num → num → num constant h : num → num → num reserve infixl `+`:65 reserve infixr `&`:70 reserve infixl `-`:65 reserve prefix `-`:100 infixl `+` := g infixl `-` := h prefix `-` := f infixr `&` := h set_option pp.notation false check -1 + 2 check 1 & 2 & 3 & 4 check 1 - 2 - 3 - 4 infixr `~~`:60 := h infixl `!!`:60 := h check 1 ~~ 2 ~~ 3 ~~ 4 check 1 !! 2 !! 3 !! 4 check 1 ~~ 2 + 3 ~~ 4