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Discussion on: We don't have to use Enums on TypeScript? 【Discussion】

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nikolaymatrosov profile image
Nikolay Matrosov •

Have you heard about const enum? It transplies to values only. E.g.

const enum Test {
    FOO = 'foo',
    BAR = 'bar'
}

const s = Test.BAR;
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results in

const s = "bar" /* BAR */;
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pontakornth profile image
Pontakorn Paesaeng •

I think it's neat. ReScript also uses this approach. Also, you need a plugin if you use Babel.

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taishi profile image
Taishi •

This is cool. I just prefer Union types but this is great if this Enums gets stripped out when compiling! Thanks @nikolaymatrosov !

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firstwhack profile image
FirstWhack • • Edited

You can't index a union type unless you're creating a lookup table based on the union so "prefer unions" is simply unviable. This is what TS does but TS can remove that lookup at compile time for "const" Enums.

Don't reinvent core features.