59 lines
1.4 KiB
JavaScript
59 lines
1.4 KiB
JavaScript
(function() {
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/*
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* object.watch polyfill
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*
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* 2012-04-03
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*
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* By Eli Grey, http://eligrey.com
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* Public Domain.
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* NO WARRANTY EXPRESSED OR IMPLIED. USE AT YOUR OWN RISK.
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*/
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// object.watch
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if (!Object.prototype.watch) {
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Object.defineProperty(Object.prototype, "watch", {
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enumerable: false
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, configurable: true
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, writable: false
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, value: function (prop, handler) {
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var
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oldval = this[prop]
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, newval = oldval
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, getter = function () {
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return newval;
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}
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, setter = function (val) {
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oldval = newval;
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return newval = handler.call(this, prop, oldval, val);
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}
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;
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if (delete this[prop]) { // can't watch constants
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Object.defineProperty(this, prop, {
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get: getter
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, set: setter
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, enumerable: true
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, configurable: true
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});
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}
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}
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});
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}
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// object.unwatch
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if (!Object.prototype.unwatch) {
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Object.defineProperty(Object.prototype, "unwatch", {
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enumerable: false
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, configurable: true
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, writable: false
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, value: function (prop) {
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var val = this[prop];
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delete this[prop]; // remove accessors
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this[prop] = val;
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}
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});
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}
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})();
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