In Defence of TypeScript Enums

I think the author missed that we are criticising typescript's enum implementation not the concept of enums in general.

They transcribe to something better defined in javascript. Typescript itself akwardly sits on the fence of almost entirely erasable and some decisions only make sense if that was the goal, like import files having a js rather than the ts extension that would point to the file in source.

Enums become javascript objects in a very leaky abstraction full of footguns. There are plenty of articles that cover these and this author seems to have written them off as 'not holding it right' but a good language feature fits in the hand naturally to stretch the analogy.

This is the problem with typescript enums, they're close enough to "normal" enums in other "real" languages that there aren't any hard edges at first glance. Luring you in with a false sense of comfort and familiarity.

Then abstraction starts leaking everywhere because it's trying to bridge between typescript and javascript and you start wishing you had either made an object (pure JS) or a literal union (pure TS).

Nice article, clearly defines the scope for enums and why it is so in TS. I had the same feeling and use enums a lit less than in C#, because of mentioned limitations, but they're still useful for right purpose

`if (color === "Red") {`

This counter example against using unions of literals would result in a compiler error ts(2367). Which only furthers the argument for using unions of literals instead.

> Enums Are Meant To Be Symbolic

And yet you can’t use symbols [1].

Author gives a valiant effort, but is defending the indefensible.

[1] https://github.com/microsoft/TypeScript/issues/18408