wren/doc/site/getting-started.markdown

^title Getting Started

Getting Wren up and running on your machine should be pretty straightforward. Tiny C programs with no dependencies are nice that way. If you're on a Unix or Mac and you can rock a command line, it's just:

:::bash
$ git clone https://github.com/munificent/wren.git
$ cd wren
$ make
$ ./wren

For Mac users, there is also an XCode project in the repo that you can use to hack on Wren. That's what I develop in. It builds fine from there but may not have the exact same build settings. The Makefile is the canonical way to compile it.

For our Windows brethren, there's still a little work to be done. Ideally, the repo would include a Visual Studio solution for building Wren. I don't have a Windows machine, but if you do, I would be delighted to take a patch for this.

Interactive mode

The above instructions will drop you into Wren's standalone interpreter in interactive mode. You can type in a line of code, and it will immediately execute it. Here's something to try:

:::dart
IO.print("Hello, world!")

Or a little more exciting:

:::dart
for (i in 1..10) IO.print("Counting up ", i)

You can exit the interpreter using good old Ctrl-C or Ctrl-D, or just throw your computer to the ground and storm off.

Running scripts

The standalone interpreter can also load scripts from files and run them. Just pass the name of the script to wren. Create a file named "my_script.wren" in your favorite text editor and paste this into it:

:::dart
for (yPixel in 0...24) {
  var y = yPixel / 12 - 1
  for (xPixel in 0...80) {
    var x = xPixel / 30 - 2
    var x0 = x
    var y0 = y
    var iter = 0
    while (iter < 11 && x0 * x0 + y0 * y0 <= 4) {
      var x1 = (x0 * x0) - (y0 * y0) + x
      var y1 = 2 * x0 * y0 + y
      x0 = x1
      y0 = y1
      iter = iter + 1
    }
    IO.write(" .-:;+=xX$& "[iter])
  }

  IO.print("")
}

Now run:

:::bash
$ ./wren my_script.wren

Neat, right? You're a Wren programmer now! The next step is to read more docs and learn your way around the language. If you run into bugs, or have ideas or questions, any and all of the following work:

• Tell me on twitter at @munificentbob.
• File a ticket at the GitHub repo.
• Send a pull request.
• Email me at robert@stuffwithstuff.com.