Presently, watch.length is always undefined because objects don't have a length property, so the for loop that follows gets called even when nothing is being watched. Object.keys() gets an array of the object's keys, which provides the length property we're after. Browser support is IE9+.
Presently,
watch.lengthis alwaysundefinedbecause objects don't have alengthproperty, so theforloop that follows gets called even when nothing is being watched.Object.keys()gets an array of the object's keys, which provides thelengthproperty we're after. Browser support is IE9+.