gistfile1.txt

let _0 = \s z. z
let _1 = \s z. s z
let _2 = \s z. s (s z)
let _3 = \s z. s (s (s z))
let _4 = \s z. s (s (s (s z)))

let succ = \n s z. s (n s z)
let plus = \m n s z. m s (n s z)
let mult = \m n s z. n (m s) z

let true  = \x y. x
let false = \x y. y
let if = \p x y. p x y