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Comment by pwdisswordfishc | Hacker News Reader

This is not TypeScript-specific, it’s a stage-3 ECMA-262 proposal.

https://github.com/tc39/proposal-explicit-resource-managemen...

It’s a shame the author insisted on it looking like C# and sabotaged attempts to combine disposal with destructuring.

Also, there is no move operator without futzing around with DisposableStack. Though that could be introduced later; it’s not a day-zero design issue.

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> and sabotaged attempts to combine disposal with destructuring.

Can you explain by what you mean by this? What would "disposal combined with destructuring" look like?

From a brief search, it looks like the semantics around destructuring and what exactly gets disposed were causing confusion?

What's the not-C#-like method that would have allowed destructuring in a better way?

TFA mentions as much: TypeScript 5.2 will introduce a new keyword - 'using' - that you can use to dispose of anything with a Symbol.dispose function when it leaves scope. This is based on the TC39 proposal, which recently reached Stage 3, indicating that it is coming to JavaScript.

Agreed with OP, the title is misleading. Typescript technically doesn't introduce any new runtime feature. This is basically a polyfill for an upcoming Javascript feature.

No, I am very familiar with JS and wasn't sure reading the article what bits were the new TC39 proposal and what bits were TS-specific. It seems, from having read it once quickly, that it's just TS adding support early to a feature that will come in JS, similar to how you could add support to async/await in your transpiler before they were commonplace by transforming them into promises back in the day. But that's definitely not a "TS new keyword".

The overwhelming share of improvements made to Java, Javascript, Typescript etc over the past decade have been inspired by C#, so I can understand why the C# terminology was front of mind.

Can you elaborate more of what combining disposal and destructuring would look like?

I’m not sure Java has taken anything from C#. Most of its recent features have been taken from ML influences.

this happens a lot in tc39 proposals unfortunately.

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