I was just about to complain how TS fails totally for typechecking backbone models or immutablejs datastructures: both situations where obj.get("foo") and obj.get("bar") return a particular type but there's no way of having TS handle that except defining them as any. But it turns out string literal types in 1.8 will make that work. And this was out since February! I should reevaluate TS for my omniscient project.