Awesome

match-js

A simple yet powerful pattern matching library for Javascript.

Let you do stuff like this (a WebWorker example):

// Create a filter that jsonify incomming data
var json_filter = Match ( 
    
    // Match if incomming object has a property called data (of type String)
    { data: String }, function(data) {
        return JSON.parse(data);
    }

);

// Hook the incoming message event with a Match statement.
onmessage = Match (

    // Parse the data through the json filter before further processing.
    json_filter,

    // Wake-up this worker service.
    'wake-up', function() {
        post('ping');
    },

    // Tell main thread that this service is ready for some work
    'pong', function() {
        post('ready');
    },

    // Do a calculation against the specified value. Simulate a heavy 
    // calculation by sending a delayed answer. 
    ['calc', Number, Number], function(no1, no2) {
        setTimeout(function() {
            post(['calc-done', no1 * no2]);
        }, 800);
    }

);

For more examples, please navigate to /examples