Hacker News Reader

Comment by nicoburns | Hacker News Reader

The one I really want is “do expressions”. I also can’t understand why anyone wants private fields over these kind of improvements. Lack of private fields in JS has literally never caused a big for me in 15 years of JavaScript development, but I have to use mutable variables and ugly if-else chains to 3 case assignment all the time!

View on HN

"do expressions" is one of the things mentioned in the Pipe Operator proposal as possibly a pre-req and one of many reasons the Pipe Operator seems to have stalled out at Stage 2 despite multiple attempts to push it past.

Personally, for the 3-case assignment I would love to see one of the smarter pattern matching "match" expression proposals make it further along over the over-generalized "do expressions". Especially now that C# has pattern matching switch expressions.

You might already know, but until do expressions land, you can use IIFEs for ifs and switches assignments:

    const isSomething = (() => {
        switch (...) {
            case ...:
                return ...
        }
    })()

They are a bit ugly but the do wonders at avoiding `let`.

Reply on news.ycombinator.com