Installing the picturing-programs teachpack

The textbook uses an optional library named (imaginatively enough) "picturing-programs". Since there have recently been a bunch of version changes beyond my control, here's my advice on how to get things working:

If you're using the August 2010 or later published version of the book with DrRacket version 5.0.99.6 or higher,
you don't need to install anything, as the library is included with DrRacket, and can be invoked by saying 
(require picturing-programs)
However, the printed book and the "worked exercises" on this web site still say 
(require installed-teachpacks/picturing-programs)
To make those "worked exercises" work in 5.1, you have two choices: you can take out the "installed-teachpacks/" from the require statements, or you can follow the same installation procedure given below for the published book and DrRacket version 5.0.0.1 through 5.0.2.
If you're using the August 2010 published version of the book with DrRacket version 5.0.0.1 through 5.0.2,
  1. Download and install DrRacket version 5.0.0.1 or higher
  2. Start DrRacket
  3. Switch languages to "Use the language declared in the source". The line
    #lang racket
    should appear in the definitions pane; leave it there.
  4. In the interactions pane, type
    (require (planet sbloch/picturing-programs:2)) exactly like that (the ":2" can be left out), and hit ENTER. After between a few seconds and a few minutes, depending on the speed of your net connection and your computer, you should get a message saying "Wrote file "picturing-programs.rkt" to installed-teachpacks directory".
  5. Switch languages to "HtDP -> Beginning Student". The #lang racket should disappear from the definitions pane; if it doesn't, delete it by hand. Hit the "Run" button near the top right corner of the DrRacket window.
  6. Add the teachpack "picturing-programs.rkt", which should be in the right-hand column of the "add teachpacks" dialogue. (Or, instead of using "Add Teachpack...", you could just type
    (require installed-teachpacks/picturing-programs)
    in the Definitions pane.) Hit "Run" again.
  7. To test the installation, type
    (big-bang (triangle 50 "solid" "blue") (on-tick rotate-cw 1) (on-draw show-it))
    in the interactions pane. You should get an animation window with a rotating blue triangle in it.
If you're using the May 2010 (or earlier) pre-release draft of the book,
  1. Download and install DrScheme version 4.2.4 or 4.2.5
  2. Start DrScheme
  3. Switch languages to "Use the language declared in the source" (which in version 4.2.4 was called "Module"). The line
    #lang scheme
    should appear in the definitions pane; leave it there.
  4. In the interactions pane, type
    (require (planet sbloch/picturing-programs:1)) exactly like that (the ":1" is important), and hit ENTER. After between a few seconds and a few minutes, depending on the speed of your net connection and your computer, you should get a message saying "Wrote file "picturing-programs.ss" to installed-teachpacks directory".
  5. Switch languages to "HtDP -> Beginning Student". The #lang scheme should disappear from the definitions pane; if it doesn't, delete it by hand. Hit the "Run" button near the top right corner of the DrScheme window.
  6. Add the teachpack "picturing-programs.ss", which should be in the right-hand column of the "add teachpacks" dialogue. (Or, instead of using "Add Teachpack...", you could just type
    (require installed-teachpacks/picturing-programs)
    in the Definitions pane.) Hit "Run" again.
  7. To test the installation, type
    (big-bang (triangle 50 "solid" "blue") (on-tick rotate-cw 1) (on-draw show-it))
    in the interactions pane. You should get an animation window with a rotating blue triangle in it.