Note that Philip Wadler was active in the Haskell committee. Early versions of Haskell did use a system like that. It was too error-prone. Monadic IO turned out to be theoretically equivalent, but without the easy ways to break it. See https://www.microsoft.com/en-us/research/wp-content/uploads/... for more details.
Note that Philip Wadler was active in the Haskell committee. Early versions of Haskell did use a system like that. It was too error-prone. Monadic IO turned out to be theoretically equivalent, but without the easy ways to break it. See https://www.microsoft.com/en-us/research/wp-content/uploads/... for more details.