There are instructions about how to get Xcode on the [Installing MacPorts](https://www.macports.org/install.php) page.
Some versions of [Xcode](http://developer.apple.com/xcode.html) are available for free on the Mac App Store.
Other versions are available through Apple's Developer website (some of these are free, but do require you to
- register with Apple as an "Apple Developer", which involves clicking to accept a legal agreement with Apple.)
+ register with Apple as an "Apple Developer", which involves clicking to accept a legal agreement with Apple).
I have an older version of this installed. If you download a recent version, email me and let me know how the
process works so I can tell others.
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or [Chibi](https://code.google.com/p/chibi-scheme). The later in that list you go, the more likely it
is that you'll have to compile the software yourself. (Thus Mac users will need Xcode.)
-Racket stands to Scheme in something like the relation Firefox stands to HTML. It's one program among others for working with the language; and many of those programs (or web browsers) permit different extensions, have small variations, and so on.
+Racket stands to Scheme in something like the relation Firefox stands to HTML. It's one program (or platform) among others for working with the Scheme language; and many of those programs (or web browsers) permit different extensions, have small variations, and so on.
Racket has several components. The two most visible components for us are a command-line interpreter named "racket" and a teaching-friendly editor/front-end named "DrRacket". You will probably be working primarily or wholly in the latter.
<!-- "racket" used to be mzscheme, "DrRacket" used to be DrScheme -->
sudo port install mzscheme
+ <!-- mzscheme v4.1.5, from March 2009; latest mzscheme is 4.2.5, from April 2010 -->
+
If you want the GUI components, I think you'll need to use the
- "Mac/without MacPorts" installation options above.
+ "Mac/without MacPorts" installation options above. Or you could try the Chicken Scheme implementation instead of Racket. This is more current.
+ To do that, type:
+
+ sudo port install chicken readline
+
+ <!-- chicken v4.8.0.2, from Feb 2013; latest available is 4.9.0.1, from Nov 2014 -->
- I recommend also typing:
+ Whether you use mzscheme or Chicken, I recommend also typing:
sudo port install rlwrap
- then if you ever use the command-line program `mzscheme` (or `racket`), you should start it by typing `rlwrap mzscheme`. This gives
+ then if you ever use the command-line program `mzscheme` (or `racket`, for that matter), you should start it by typing `rlwrap mzscheme` (or whatever). This gives
you a nice history of the commands you've already typed, which you can scroll up and down in with your
keyboard arrows.
sudo apt-get rlwrap
- then if you ever use the command-line program `mzscheme` (or `racket`), you should start it by typing `rlwrap mzscheme`. This gives
+ then if you ever use the command-line program `mzscheme` (or `racket`), you should start it by typing `rlwrap mzscheme` (or whatever). This gives
you a nice history of the commands you've already typed, which you can scroll up and down in with your
keyboard arrows.