exmple.js

// My object err.. function, ya know.
function MyObject(options) {
  if (!options) {
    options = {};
  }

  var default_options = {
    foo: 'foo',
    bar: 'bar'
  };

  // Do awesome magic stuff here...
  // ( With libs: $.extend(), _.extends() )
  // However, I want it without libs. And allowed with IE8.
  // I'd preffer a pattern over a polyfill function
  //
  this.options = default_options << options; // fill in the blanks here.
}


// I'd use it like so:
var a = new MyObject();
var b = new MyObject({foo: 'foobar'});
var c = new MyObject({foo: 'foobar', bar: 'barfoo'});

a.options; // => {foo: 'foo', bar: 'bar'}
b.options; // => {foo: 'foobar', bar: 'bar'}
c.options; // => {foo: 'foobar', bar: 'barfoo'}