TypeScript Won. Here's What That Actually Bought Us.

Nobody seriously argues about adopting TypeScript anymore. New frontend projects default to it; the holdouts are legacy codebases and the occasional throwaway script. The debate is over, TypeScript won. But "won" is the boring part. The interesting part is what types turned out to be good for — which is more, and different, than the original pitch of "catch typos before runtime." Types are the cheapest documentation you'll never have to update A function signature is documentation that can't go…