;; -------------------------------------------------------------------------
;; an example using a Racket generator to create an infinite list
;; -------------------------------------------------------------------------

#lang racket
(require racket/generator)

(define squares
  (generator ()
    (letrec ((loop (lambda (n)
                     (yield (* n n))
                     (loop (add1 n)))))
      (loop 1))))

;; > (squares)
;; 1
;; > (squares)
;; 4
;; > (squares)
;; 9
;; > (squares)
;; ...
;; -------------------------------------------------------------------------