Catspeak

Catspeak is the spiritual successor to the long dead execute_string function from GameMaker 8.1, but on overdrive.

Use the built-in Catspeak scripting language to expose safe and sandboxed modding APIs within GameMaker projects, or bootstrap your own domain-specific languages and development tools using the back-end code generation tools offered by Catspeak.

Compile performant scripts from plain-text...

// parse Catspeak code
var ir = Catspeak.parseString(@'
  let catspeak = "Catspeak"

  return "hello! from within " + catspeak
');

// compile Catspeak code into a callable GML function
var getMessage = Catspeak.compileGML(ir);

// call the Catspeak code just like you would any other GML function!
show_message(getMessage());

...without giving modders unrestricted access to your sensitive game code:

var ir = Catspeak.parseString(@'
  game_end(); -- heheheh, my mod will make your game close >:3
');

// calling `badMod` will throw an error instead
// of calling the `game_end` function
try {
  var badMod = Catspeak.compileGML(ir);
  badMod();
} catch (e) {
  show_message("a mod did something bad!");
}.