[seanclayton]

Typescript provided none of those besides sum types.

[cies]

and sum types bolted on, it something else from sum types that are idiomatic and used throughout all of the std lib.

that's my main gripe with TS: it's bolted on nature.

that's why I prefer a clean slate (like Elm, Rust, F#/Fable, ReasonML/ReScript, PureScript, or this "Grain" project)