"And why do you need type safety? Because you are used to?"
Er. Well, if you like driving a car with no seatbelts, crumple zone, or airbags, I guess that's fine with me. But when I get in a car, I buckle up.
Static type systems prevent you from expressing certain programs (I think this is a good thing, but not everyone does).
A better analogy would be antilock brakes or understeer - safer but prevents you from doing certain things.
(both you and the parent comment are kinda doing this)
The
"If you don't like JavaScript, just use CoffeeScript like everyone else! What's wrong with you?"
This is better than nothing, sure, because your code is first checked in OCaml but once the code is running, it does it according to Javascript rules.
I imagine there could be subtle bugs introduced during this process (e.g. your OCaml code manipulate integers, but Javascript has numbers, a.k.a. double floats, as far as I know).
Here, the compiler emits (a subset of) javascript which are assumed to have a semantics, and we trust the browser engine to execute it according to the semantic.
Of course we don't assume the semantic of javascript to be sane, we just assume it follows the spec (and we emit accordingly).
Any code generation machinery is subject to subtle bugs and especially so the flesh and bones kind ;)