Emacs function to help create a TDD loop when writing SML

sml-tdd-loop.el

(defun restart-sml ()
  (sml-prog-proc-switch-to)
  (end-of-buffer)
  (comint-delchar-or-maybe-eof 0))

(defun run-sml-tests-now ()
  (let* ((code-file-name
           (replace-regexp-in-string "_tests" "" (buffer-file-name)))
	 (test-file-name
	   (replace-regexp-in-string "\.sml" "_tests.sml" code-file-name)))
    (sml-mode)
    (sml-prog-proc-load-file code-file-name)
    (sml-prog-proc-load-file test-file-name)
    (windmove-up)))

(defun run-sml-tests ()
  (interactive)
  (restart-sml)
  (windmove-up)
  (run-with-idle-timer 0.5 nil 'run-sml-tests-now))

(global-set-key (kbd "C-c C-t") 'run-sml-tests)

Thanks it will be really useful for me!