watch-value

console = console || {}; // just in case
console.watch = function(oObj, sProp) {
   sPrivateProp = "$_"+sProp+"_$"; // to minimize the name clash risk
   oObj[sPrivateProp] = oObj[sProp];

   // overwrite with accessor
   Object.defineProperty(oObj, sProp, {
       get: function () {
           return oObj[sPrivateProp];
       },

       set: function (value) {
           //console.log("setting " + sProp + " to " + value); 
           debugger; // sets breakpoint
           oObj[sPrivateProp] = value;
       }
   });
}