2 ms·

Nominal type systems are pretty much better across the board IMO. Much safer and much less to keep in your head. Modern langs like Rust or F# have very complete

• adamscybot 2y ago
  One language that comes to mind is ReasonML. It doesn't have runtime checking. It's structural and compile time, but the guarantees are supposedly cast iron. https://reasonml-old.github.io/guide/language/type#design-decisions https://reasonml-old.github.io/guide/language/type#design-de... type thing = | String(string) | Bool(bool); let arr: list(thing) = []; let add = (item: thing, dst: list(thing)): list(thing) => { switch (item) { | String(s) => dst @ [String(s)] | Bool(b) => dst @ [Bool(b)] }; }; let newList = add(String("asd"), arr); This doesn't work, since the dst array has to be one that can contain both string and bool in the first place.