bixuanzju

(defun isml ()
  "If sml repl exists, then restart it else create a new repl."
  (interactive)
  (when (get-buffer "*sml*")
    (with-current-buffer "*sml*"
      (when (process-live-p "sml")
        (comint-send-eof)))
    (sleep-for 0.2))
  (sml-run "sml" ""))

bixuanzju

{-# LANGUAGE RankNTypes #-}


newtype BST k v = Roll
  { unroll :: forall r. r -> (k -> v -> r -> r -> r) -> r
  }

-- Two constructors
leave :: BST k v
leave = Roll const