There's nothing "modern" about the C-style curly brace and semi-colon syntax in Reason. In fact, the rise of Python and it's lightweight syntax means that C-style languages are starting to look dated.
Indentation-sensitive syntax is totally obsolete in a world with autoformatters. In addition, with this kind of syntax you also lose the ability to have your code autoformatted in certain situations. Here's a trivial example to illustrate the point:
def example():
x = 5
print("Hello world")
What's the mistake here? Depending on whether the print is part of the function, it should either be indented or have a newline before it. The point is you (and any formatting tool) can't know what the horizontal alignment of this code should be just by examining the vertical line order. You can only determine this by knowing (or reanalyzing) the semantics of the code. During a refactor where you're moving around lots of code, this can be a significant PITA. However, in the JS example,
function example() {
let x = 5
console.log("Hello world")
}
it's unambiguous what the mistake is because you can determine the correct formatting entirely from the line order, without having to know anything about the code's semantics.
This is a really good point, but one still doesn't need curly braces and semis. Despite having a lightweight syntax, OCaml isn't indentation sensitive, so doesn't suffer from this. The Ocamlformat tool also works really well.
> OCaml isn't indentation sensitive, so doesn't suffer from this
True, I was just making the point that the lightweight syntax of indentation-sensitive languages like Python can be problematic. I don't know how OCaml is able to achieve this style of syntax without the use of significant indentation, but it is impressive.
