Hi,

(unfortunately Twitter is again doesn't fit for a more than 140 ch discussion, so moving here)

I'd like to still notice the possibility of accepting the "almost everything is expression" approach for JS. After Erlang I very often miss this possibility.

The idea is to make most of current complex statements as expressions.

Dave mentioned the proposal with `do { ... }` -- yeah, it's fine, but much nicer is to have "all of them" as expressions. CoffeeScript adopted this style as well.

Besides, I'd like to note, that the thing is not just "interesting theoretical stuff", but really is very convenient and useful in practice.

Examples:

1. Switch-expression (as addition, I eliminated `break`)

let a = switch (foo) {
  case 10: 100;
  default: 200;
};

2. If-expression:

let a = if (foo) {
  print('a is foo');
  foo;
} else {
  // do some longer stuff
};

We of course already have for years the expression sugar for this -- ? : operator, but it doesn't allow to conveniently have longer bodies of consequent and alternative nodes of if-expression.

3. Try-expressions:

let a = try {
  // do dangerous stuff
  "ok  value";
} catch (e) {
  "default value";
};

Another note -- I also made `return` optional (if need to exit from the middle -- we can use it; BTW, it's a lack of Erlang -- we can't exit from the middle, but should build our blocks in the needed way).

4. What else? ... Perhaps some others.

Brendan and Dave mention explicit semicolon. Yes, it's seems so by the grammar (though, have to check more precisely), but it can be acceptable price.

P.S:

Regarding Dave's `do { .. }` -- we may omit `do` and just evaluate the block.

let a = {
  print('doing stuff');
  100;
};

It's of course seems ambiguous with an object initialiser (at first glance), but it's only at first glance. Obviously there is a code inside to evaluate.

Cheers,
Dmitry.
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