Welcome

Thanks for coming!

Magpie is a small dynamically-typed programming language built around patterns, classes, and multimethods. From functional languages, it borrows first-class functions, closures, expressions-for-everything, and quotations. Its most novel feature is probably an extensible syntax. It runs on the JVM.

It looks a bit like this:

// Generates the sequence of turns needed to draw a dragon curve.
// See: http://en.wikipedia.org/wiki/Dragon_curve
def dragon(0, _)
    ""
end

def dragon(n is Int, turn)
    dragon(n - 1, "R") + turn + dragon(n - 1, "L")
end

print(dragon(5, ""))

Its goal is to let you write code that's beautiful and easy to read, and to allow you to seamlessly extend the language and libraries as you see fit.

Where We're At

Here's the deal. Magpie is very young. The egg has been laid, but still hasn't quite cracked open yet. Everything described here is implemented and working now, but lots of stuff is missing, buggy, or likely to change. I wouldn't entrust it with my lunch money if I were you.

If you just want a language to use, this is bad news. But if you want a language to contribute to, this is great news! Lots of interesting important decisions have yet to be made, and there's lots of fun stuff that needs coding. I'd love to have you involved.

Getting Started

It should be pretty easy to get it up and running. You'll need to:

1. Pull down the code. It lives here: https://github.com/munificent/magpie

2. Build it. The repo includes an Eclipse project if that's your thing. If you rock the command-line, you can just do:

   $ cd magpie
   $ ant jar
   

3. Run it. Magpie is a command line app. After building the jar, you can run it by doing:

   $ ./magpie
   

If you run it with no arguments, it drops you into a simple REPL. Enter a Magpie expression and it will immediately evaluate it. Since everything is an expression, even things like class definitions, you can build entire programs incrementally this way. Here's one to get you started:

    for i in 1 to(20) do print("<your name> is awesome!")

If you pass an argument to the app, it will assume it's a path to a script file and it will load and execute it:

    $ ./magpie script/Hello.mag

Where to Go From Here

Since you've made it this far, you must be interested. You can learn more about the language from the Magpie posts on my blog. (Note that the language has changed dramatically over time, so the older a post is, the less likely it is to still be relevant.)

To get a sense of the language itself, take a look at some examples, the standard library or executable language specification, written in Magpie.

If you have questions or comments, the mailing list here is a good place to start. You can file bugs or issues on github. If you want some live interaction, there's an IRC channel on freenode: #magpie-lang.

Cheers, and have fun playing with it!