[robpalmer]

For our purposes, the primary problem with enums is not the runtime overhead. The runtime code for TS enums is a little verbose but it's not huge. The semantics are a little wacky as described in Axel Rauschmeyer's article: https://2ality.com/2020/01/typescript-enums.html

The primary problem is the potential conflict with future ECMAScript. Multiple TypeScript team members have talked about how this feature is now regretted. The article features Orta's famous meme-slide communicating why runtime features (specifically calling enum) should not really be in the TypeScript language. Anders talked about it three weeks ago during the Q&A session at TSConf: https://www.youtube.com/watch?v=vBJF0cJ_3G0

enum is highly unlikely to be removed from TypeScript because of the strong commitment to backwards compatibility. But that doesn't mean we should encourage proliferation. Especially when many use-cases can be served more simply by string unions.

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