#lang racket
(define (infinity)
  (+ 1 (infinity)))

(define (fst x y) x)

(define lazy-infinity (delay(infinity)))
;(fst 3 (infinity))
(force (fst 3 lazy-infinity))
(fst 3 lazy-infinity)
(define res (delay (+ 2 5)))
(force res)
(force (delay (fst 3 lazy-infinity)))