#lang s-exp rosette

(require "reactive.rkt")

(require "pulser-class.rkt")

(define (flip c)

(if (equal? c (color "blue")) (color "red") (color "blue")))

(define colored-pulser%

(class pulser%

(inherit milliseconds image previous)

(super-new)

; this constraint is inherited:

; (always (equal? (circle-radius (image)) (+ 60 (* 50 (sin (seconds))))))

(when (zero? (remainder (milliseconds) 2000))

(assert (equal? (circle-color (image))

(flip (previous (circle-color (image)))))))

(send this solve)))

(define p (new colored-pulser%))

(make-viewer p #:title "Colored pulser")