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Comment by baq | Hacker News Reader

Maybe argue for enum being added to ecmascript instead?

But why? The feature offers almost no benefit in TS at this point over other existing features, has no function in JS other than TS compatibility, and is increasingly flaky in TS itself. Adding more complexity to JS rather than simplifying TS by deprecating this old, janky foot gun and educating devs on better alternatives seems like moving in the wrong direction.

TypeScript didn't invent enums. They exist because it really sucks to write out:

    const MyEnum = {
      x: 1,
      y: 2,
      z: 3,
      // etc
    }

instead of

    enum MyEnum {
      x = 1,
      y,
      z,
      // etc
    }

when you want a series of constants each with a unique value but don't particularly care what that value is.

TypeScript's enums are particularly weak compared to enums in other languages precisely because there's no JS support for enums. Modern languages have support for ADTs.

TypeScript enums were added in large part because union types didn't exist at the time. Those don't require you to write out anything like the above. The only case where you would need to write out number literals like that would be if you specifically wanted the values to be numbers for some reason, rather than interned strings.

In the vast majority of cases, there's no good reason to do that.

Edit: But no, the reason enums in TypeScript suck is not that JS doesn't have them. That wouldn't fix anything other than the type stripping problem. The main reason that they suck is that they use a completely different type model from the rest of the language.

enums are a feature of most programming languages. It doesn't matter to me why TypeScript had to add them, just like it doesn't matter why JS has functions or if statements.

90% of the enums I use are regular integer enums. I don't get much use out of string enums, as you say union types do that job just fine.

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