When you write Javascript, do you mean TypeScript, AtScript, something else? There's no type checking in JS, and there is no metaprogramming support in JS, let alone of the quality it can be found in Haxe.

Besides that, the type system of Haxe is far more expressive than those of most languages that also compile to JS. Ocaml, Scala and Haskell are the better known languages that are actual competitors in that regard.