WeScheme

WeScheme is a browser-based version of Racket. It works well for at least the first semester of Intermediate Computer Science.

Special notes for WeScheme users

You can use WeScheme if you cannot install DrRacket. For example, if you have a Chromebook for your home computer.

There are a few differences:

• Omit the (require picturing-programs) line.

• (Chapter 1) See the Chapter 1 WeScheme starter code.

• (Chapter 3) Use the Chapter 3 WeScheme starter code.

  • Instead of copy and pasting in a picture, you need to copy the link for the image and use bitmap/url like this:

(bitmap/url "https://www.what-dog.net/Images/faces2/main004.jpg")

• (Chapter 6) Inside big-bang you need to use the phrase to-draw instead of on-draw that we use in DrRacket.

  (define (draw-handler model) 
      (overlay model (empty-scene 300 200)))
  (define (tick-handler model) 
      (scale 1.01 model))
  
  (big-bang (circle 10 "solid" "green")
            (on-tick tick-handler)
            (to-draw draw-handler))