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Structs for JavaScript inspired by Ruby

Ruby Structs are an awesome way to add several attributes to a class. Inspired by these, Strukt provides a similiar minimalistic API for JavaScript in the browser and in Node.


  • Node: $ npm install strukt

    var Struct = require('strukt');
  • Browser: Grab lib/strukt.js and include it in your HTML document.

    A global Struct function will be added. AMD and CommonJS loaders are also supported.

Basic structs

Simple. Pass the parameters you want to Struct, a new constructor function will be returned.

var Point = new Struct('x', 'y');
var p = new Point(42, 1337);
p.x; // 42 
p.y; // 1337 

Prefer CoffeeScript?

class Point extends new Struct 'x''y'
  # More class logic 
= new Point 421337;
p.# 42 
p.# 1337 

Explicit structs

Explicit is better than implicit. The Zen of Python

Explicits structs are pretty much the same thing, but you pass an object to the returned constructor.

var Person = new Struct.Explicit('forename', 'surname');
var john = new Person({
    forename: 'John',
    surname: 'Doe'
john.forename; // 'John' 
john.surname; // 'Doe' 

Constructor functions

Maybe you'd like to add a constructor function to your Struct. If the last argument of Struct or Struct.Explicit is a function it'll used as a constructor function.

var Person = new Struct.Explicit('forename', 'surname', function () {
    alert('Welcome ' + this.forename + " " + this.surname);
new Person({
    forename: 'John',
    surname: 'Doe'
}); // Will alert 'Welcome John Doe' 

Adding properties to the prototype

Struct and Struct.Explicit return functions, so you can just add properties to the prototype as always.

var Point = new Struct("x", "y");
Point.prototype.equals = function (pt) {
    return this.x == pt.x && this.y == pt.y;

Test suite

Visit spec/index.html in your browser to run the test suite.

Alternatively you can install testacular and enjoy the awesomeness

$ testacular start

It will launch several browsers and run the tests again if a a spec or the library code changes.