call-with-region-or-line.el

;;; 結局採用したやつ
(defun call-with-region-or-line (func-symbol)
  "Call FUNC-SYMBOL with marked region or current line.

If the region is active, beggining and end of region is used for the function
 arguments, othewise current line is used."
  (if (region-active-p)
      (funcall func-symbol (region-beginning) (region-end))
    (let* ((begin (line-beginning-position))
           (end (1+ (line-end-position))))
      (funcall func-symbol begin end))))
(use-package sml-mode
  :config
  (defun sml-prog-proc-send-region-or-line ()
  "Call REPL with active region or current line."
  (interactive) (call-with-region-or-line #'sml-prog-proc-send-region))
  :bind (:map sml-mode-map ("C-c C-r" . sml-prog-proc-send-region-or-line)))

;;;=================================================================

  ;;; 行頭に右を足すと動く -*- lexical-binding: t; -*-
  ;;; :bindと相性が悪く、bind-keyべた書きしている
  (defun call-with-region-or-line (func-symbol)
    ""
    (lambda () (interactive)
      (if (region-active-p)
          (funcall func-symbol (region-beginning) (region-end))
        (let* ((begin (line-beginning-position))
               (end (1+ (line-end-position))))
          (funcall func-symbol begin end)))))
  (bind-key "C-c C-r" (call-with-region-or-line #'sml-prog-proc-send-region)
            sml-mode-map)
            
;;;=================================================================

  ;;; dynamic bindingでも動く
  ;;; けど、毎回(lambda () (interactive) ...を書く必要がある
  (defun call-with-region-or-line (func-symbol)
    ""
    (if (region-active-p)
        (funcall func-symbol (region-beginning) (region-end))
      (let* ((begin (line-beginning-position))
             (end (1+ (line-end-position))))
        (funcall func-symbol begin end))))
  :bind (:map sml-mode-map
              ("C-c C-r" .
               (lambda () (interactive)
                 (call-with-region-or-line #'sml-prog-proc-send-region))))