Knockout-2.2.0, subscribe get value before change AND new value

Question

jsfiddle link: http://jsfiddle.net/T8ee7/

When I call Knockout\'s subscribe method is there a way I can get both the previous and new value? Right now, I can only call g

Answer 1

This seems to work for me

ko.observable.fn.beforeAndAfterSubscribe = function (callback, target) {
 var _oldValue;
 this.subscribe(function (oldValue) {
     _oldValue = oldValue;
 }, null, 'beforeChange');
   this.subscribe(function (newValue) {
     callback.call(target, _oldValue, newValue);
 });
}; 

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