Sweet Actors

A set of sweet.js macros for writing actors in a Scala-like syntax.

Examples

The actor keyword creates a new actor prototype which can then be instantiated. The body of an actor includes different cases depending on the message being received. Additionally, sending messages to actors with ~ automatically passes a reference to the message origin which is available as sender.

    var a1,a2;

    actor A1 {
        "start" => {
            for (var i = 0; i < 100; i++) {
                a2 ~ "ping";
            }
            a2 ~ "stop";
        },
        "pong" => { console.log("pong"); }
    }

    actor A2 {
        "ping" => {
            console.log("ping");
            sender ~ "pong";
        },
        "stop" => { console.log("stop"); }
    }

    a1 = new A1();
    a2 = new A2();
    a1 ~ "start";

Messages consist of an arbitrary number of JavaScript values. Similar to Scala's pattern matching, the actor uses a variant of multiple dispatch which matches arguments with literals and binds any free variables.

    actor Greeter {
        "greet", someone => {
            // Ask for the name first
            someone ~ "who?";
        },
        "name!", "Jacques" => {
            // Jacques has its own routine
            sender ~ "hello", "Bonjour Jacques!";
        },
        "name!", name => {
            // All others will receive a normal greeting
            sender ~ "hello", "Hello " + name + "!";
        }
    }

    actor TestPerson {
        "name!", newName => {
            // I'm now called newName
            this.name = newName;
        },
        "who?" => {
            // Telling the sender my name
            sender ~ "name!", this.name;
        },
        "hello", msg => {
            // Print whatever was told me.
            console.log(msg);
        }
    }

Installation

Assuming that grunt is installed...

npm install

Tests

Tests are run with mocha.

npm test

Debugging

I recommend node-inspector.

npm install -g node-inspector
node-inspector &

Debugging the application:

node --debug-brk $(which grunt)

If source-maps support is working, you will see the actual source file and not the generated code.