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0 pointsbrundolf4y ago0 comments

I haven’t read the full post, but what’s the benefit of adding language support for records and tuples at this point? My understanding is that engines already optimize the objects/arrays version of those concepts pretty well, and TypeScript enforces the semantics on the dev side.

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Zababa4y ago

> My understanding is that engines already optimize the objects/arrays version of those concepts pretty well

They don't, using libraries that guarantee runtime immutability has a heavy performance cost in JS currently.

brundolfOP4y ago

By “object approach” I just meant “making a bunch of objects with the same shape”. I’ve read that V8 can optimize these into flat structs.

Is immutability part of the proposed standard? And if so, what’s the benefit over using Object.freeze?

Zababa4y ago

Immutability is the whole point of records and tuples. You can read more about them on the proposal: https://github.com/tc39/proposal-record-tuple.

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0 pointsbrundolf4y ago0 comments

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Zababa4y ago

> My understanding is that engines already optimize the objects/arrays version of those concepts pretty well

They don't, using libraries that guarantee runtime immutability has a heavy performance cost in JS currently.

brundolfOP4y ago

By “object approach” I just meant “making a bunch of objects with the same shape”. I’ve read that V8 can optimize these into flat structs.

Is immutability part of the proposed standard? And if so, what’s the benefit over using Object.freeze?

Zababa4y ago

Immutability is the whole point of records and tuples. You can read more about them on the proposal: https://github.com/tc39/proposal-record-tuple.

1 more reply

j / k navigate · click thread line to collapse