[mrgriffin]

Not OP, but my understanding is that it's a common approach in Idris. Here's the creator of the language deriving the implementation of zipWith without writing any code: https://www.youtube.com/watch?v=X36ye-1x_HQ&t=1274

Some other examples include:

- Haskell: https://hackage.haskell.org/package/ghc-justdoit

- Scala: https://github.com/TypeChecked/alphabet-soup

- Agda: https://youtu.be/3U3lV5VPmOU?t=3159

I was under the impression that justDoIt comes from Scala, but I can't find a reference for that.