Tom Van Cutsem (2014-12-21T19:11:05.000Z)
d at domenic.me (2015-01-05T20:42:51.522Z)
Adding Reflect.{isCallable, isConstructor} looks reasonable to me. If the spec needs these internally, chances are JS developers will need them at one point. And as you note, typeof === "function" is a common work-around in use today. So +1.