Sounds like 'Typed Holes'[1] in the Haskell ecosystem. [1]: https://downloads.haskell.org/~ghc/7.10.3-rc1/users_guide/typed-holes.html https://downloads.haskel

Sounds like 'Typed Holes'[1] in the Haskell ecosystem. [1]: https://downloads.haskell.org/~ghc/7.10.3-rc1/users_guide/typed-holes.html https://downloads.haskell.org/~ghc/7.10.3-rc1/users_guide/ty...