Object.observe()

	var model = {};
	// Which we then observe
	Object.observe(model, function(changes){
	// This asynchronous callback runs
	changes.forEach(function(change) {
	// Letting us know what changed
	console.log(change.type, change.name, change.oldValue);
	});
	});
	Object {}
	model.name = "yannos"
	VM159:11 add name undefined
	"yannos"
	model.name = "yannis"
	VM159:11 update name yannos
	"yannis"
	// If you don’t specify a list of accept types to O.o(), it defaults to the "intrinsic"
	// object change types ("add", "update", "delete", "reconfigure", "preventExtensions"
	// (for when an object becoming non-extensible isn’t observable)).
	// Like earlier, a model can be a simple vanilla object
	var model = {
	name: 'yannis',
	surname: 'kolovos'
	};
	// We then specify a callback for whenever mutations
	// are made to the object
	function observer(changes){
	changes.forEach(function(change, i){
	console.log(change);
	})
	};
	// Which we then observe, specifying an array of change
	// types we’re interested in
	Object.observe(model, observer, ['delete']);
	// without this third option, the change types provided
	// default to intrinsic types
	model.name = 'yannos';
	// note that no changes were reported
	VM562:4 "yannos"
	delete model.name
	VM562:4 Object {type: "delete", object: Object, name: "name", oldValue: "yannos"}
	true

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