Implicit filtering of properties that are not an object's own in `for (property in object)' and `for each (value in object)' loops.

iter-own-props.js

/*jslint white: true, onevar: true, undef: true, nomen: true, eqeqeq: true, plusplus: true, bitwise: true, regexp: true, strict: true, newcap: true, immed: true */

// usage example: http://gist.github.com/189580

"use strict";

(function () {
	var objProto = Object.prototype,
	hasOwnProp = objProto.hasOwnProperty,
	iterMethod = "__iterator__",
	iterator = function (flag) {
		var prop;
		
		delete objProto[iterMethod];
		
		for (prop in this) {
			if (hasOwnProp.call(this, prop)) {
				yield flag ? prop : this[prop];
			}
		}
		
		objProto[iterMethod] = iterator;
	};
	objProto[iterMethod] = iterator;
}());