If you want something that is similar but looks better and more mature, check out Mint (mint-lang.com - I'm the author)
8 years and haven't hit 1.0, that's a bit of torture, no?
Yes, it is a bit of torture :) however I'm getting there. Context (https://mint-lang.com/news/context) was the last bigger feature before 1.0 which I'm planning to release this year.
- TypeScript syntax comparison is here: https://mint-lang.com/from/typescript
- The feature matrix which compares languages features is here: https://mint-lang.com/feature-matrix
I hope you find those helpful :)
edit: by the way TypeScript supports both ADTs (through tagged unions) as well as exhausting pattern matching (on tagged unions, but an alternative can be using `instanceof`).
But you are right, I'll change TypeScript to say it's partially supported.