prelude definition Prop := Type.{0} inductive true : Prop := intro : true inductive false : Prop constant num : Type inductive prod (A B : Type) := mk : A → B → prod A B infixl ` × `:30 := prod variables a b c : num section local notation `(` t:(foldr `, ` (e r, prod.mk e r)) `)` := t check (a, false, b, true, c) set_option pp.notation false check (a, false, b, true, c) end section local notation `(` t:(foldr `, ` (e r, prod.mk r e)) `)` := t set_option pp.notation true check (a, false, b, true, c) set_option pp.notation false check (a, false, b, true, c) end section local notation `(` t:(foldl `, ` (e r, prod.mk r e)) `)` := t set_option pp.notation true check (a, false, b, true, c) set_option pp.notation false check (a, false, b, true, c) end section local notation `(` t:(foldl `, ` (e r, prod.mk e r)) `)` := t set_option pp.notation true check (a, false, b, true, c) set_option pp.notation false check (a, false, b, true, c) end