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

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)