Earlier quoted context omitted.
See PureScript and Elm. Dart is surely more concise, but not very innovative.
Elm is extremely exciting. Whenever I get frustrated with js I fire up an elm app I have been working on just to see those beautiful compiler errors. Seriously though, Elm's error reporting is best in class.
Not just because of the compiler errors, but also because of its other limitations, like having your effects isolated via `Cmd`s and ports.