--- /dev/null
+;;; sed-mode.el --- Major mode to edit sed scripts -*- lexical-binding: t; -*-
+
+;; Copyright (C) 2016 Free Software Foundation, Inc.
+
+;; Author: Stefan Monnier <monnier@iro.umontreal.ca>
+;; Version: 0
+;; Keywords:
+
+;; This program is free software; you can redistribute it and/or modify
+;; it under the terms of the GNU General Public License as published by
+;; the Free Software Foundation, either version 3 of the License, or
+;; (at your option) any later version.
+
+;; This program is distributed in the hope that it will be useful,
+;; but WITHOUT ANY WARRANTY; without even the implied warranty of
+;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+;; GNU General Public License for more details.
+
+;; You should have received a copy of the GNU General Public License
+;; along with this program. If not, see <http://www.gnu.org/licenses/>.
+
+;;; Commentary:
+
+;; If you need this major mode, you might also want to
+;; consider spending some time with `M-x doctor'.
+
+;;; Code:
+
+(require 'cl-lib)
+(require 'smie)
+
+(defgroup sed-mode nil
+ "Major mode to edit sed code."
+ :group 'programming)
+
+
+(defvar sed-mode-syntax-table
+ (let ((st (make-syntax-table)))
+ (modify-syntax-entry ?# "<" st)
+ (modify-syntax-entry ?\n ">" st)
+ (modify-syntax-entry ?\\ "." st)
+ st))
+
+(defconst sed-commands ":=aiqQrRbcdDhHgGlnNpPstTwWxy")
+
+(eval-and-compile
+ (defconst sed-command-prefix-regexp "\\(?:^\\|[$/0-9;]\\)[ \t]*")
+ (defconst sed-address-prefix-regexp "\\(?:^\\|[,;]\\)[ \t]*"))
+
+(defconst sed-label-regexp "[[:alnum:]]+")
+
+(defun sed-syntax-propertize (beg end)
+ (goto-char beg)
+ (sed-syntax-propertize-string end)
+ (funcall
+ (syntax-propertize-rules
+ ("\\\\$"
+ (0 (unless (nth 8 (save-excursion (syntax-ppss (match-beginning 0))))
+ (put-text-property (match-beginning 0) (match-end 0)
+ 'syntax-table (string-to-syntax "|"))
+ (sed-syntax-propertize-string end)
+ nil)))
+ ((concat "\\(?:" sed-address-prefix-regexp
+ "\\(?:\\(?1:/\\)\\|\\\\\\(?1:.\\)\\)"
+ "\\|" sed-command-prefix-regexp "[sy]\\(?1:.\\)"
+ "\\)")
+ (0 (unless (nth 8 (save-excursion (syntax-ppss (match-beginning 0))))
+ (put-text-property (match-beginning 1) (match-end 1)
+ 'syntax-table (string-to-syntax "\""))
+ (sed-syntax-propertize-string end)
+ nil))))
+ (point) end))
+
+(defun sed-syntax-propertize-string (end)
+ (let* ((ppss (syntax-ppss))
+ (c (nth 3 ppss)))
+ (when c
+ (let ((count (cond
+ ((or (eq c t)
+ (not (memq (char-before (nth 8 ppss)) '(?s ?y))))
+ 1)
+ (t 2))))
+ (goto-char (1+ (nth 8 ppss)))
+ (when (re-search-forward
+ (if (eq c t) "[^\\]\n" (regexp-quote (string c)))
+ end 'move count)
+ (put-text-property (1- (match-end 0)) (match-end 0)
+ 'syntax-table
+ (if (eq c t) (string-to-syntax "|")
+ (string-to-syntax "\""))))))))
+
+(defun sed--font-lock-command (cmd)
+ (unless (nth 8 (syntax-ppss))
+ (pcase cmd
+ (?: (if (looking-at (concat "[ ]*\\(" sed-label-regexp "\\)"))
+ (put-text-property (match-beginning 1) (match-end 1) 'face
+ font-lock-function-name-face)))
+ ((or ?b ?t ?T)
+ (if (looking-at (concat "[ ]*\\(" sed-label-regexp "\\)"))
+ (put-text-property (match-beginning 1) (match-end 1) 'face
+ font-lock-constant-face))))
+ font-lock-keyword-face))
+
+(defconst sed-font-lock-keywords
+ `((,(concat sed-command-prefix-regexp "\\([" sed-commands "]\\)")
+ (1 (sed--font-lock-command (char-after (match-beginning 1)))))))
+
+(defconst sed-smie-grammar nil)
+
+(defun sed-smie-rules (kind token)
+ (pcase (cons kind token)
+ (`(:list-intro . ,_) t)
+ ))
+
+;;;###autoload (add-to-list 'auto-mode-alist '("\\.sed\\'" . sed-mode))
+
+;;;###autoload
+(define-derived-mode sed-mode prog-mode "Sed"
+ "Sed editing mode."
+ ;; (setq-local font-lock-support-mode nil) ;; To help debugging.
+ (setq-local comment-start "# ")
+ (setq-local comment-end "")
+ (setq-local parse-sexp-lookup-properties t)
+ (setq-local open-paren-in-column-0-is-defun-start nil)
+ (setq-local syntax-propertize-function #'sed-syntax-propertize)
+ (setq-local font-lock-defaults '(sed-font-lock-keywords))
+ (smie-setup sed-smie-grammar #'sed-smie-rules
+ ;; :backward-token #'sm-c-smie-backward-token
+ ;; :forward-token #'sm-c-smie-forward-token
+ )
+ ;; Backslash auto-realign.
+ ;; (add-hook 'after-change-functions #'sm-c--bs-after-change nil t)
+ ;; (add-hook 'post-command-hook #'sm-c--bs-realign nil t)
+ ;; (setq-local add-log-current-defun-header-regexp sm-c--def-regexp)
+ ;; (setq-local imenu-generic-expression `((nil ,sm-c--def-regexp 1)))
+ )
+
+(provide 'sed-mode)
+;;; sed-mode.el ends here