Include peg grammar mode.

init.el

@@ -15,6 +15,12 @@
 (add-to-list 'load-path "~/.emacs.d/vendor/coffee-mode")
 (require 'coffee-mode)
 
+;; peg mode
+(autoload 'peg-mode "peg-mode" "Mode for editing PEG grammar files" t)
+(setq auto-mode-alist
+      (append '(("\\.peg$"    . peg-mode))
+              auto-mode-alist))
+
 ;; clojure mode
 (add-to-list 'load-path "~/.emacs.d/vendor/coffee-mode")
 (require 'clojure-mode)

peg-mode.el

@@ -0,0 +1,151 @@
+;;; peg-mode.el --- emacs mode for editing PEG grammar files
+
+;; Copyright (C) 2008  Utz-Uwe Haus <[email protected]>
+
+;; This file 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 2, or (at your option)
+;; any later version.
+
+;; This file 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 GNU Emacs; see the file COPYING.  If not, write to
+;; the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+;; Boston, MA 02111-1307, USA.
+
+;;; Commentary:
+;; This file provides a major mode for editing PEG grammar files.
+;; It includes font-lock definitions and commands for
+;; controlling indentation, re-indenting by subdivisions.
+;;
+;; To use, put the following in your .emacs:
+;;
+;; (autoload 'peg-mode "peg-mode" "Mode for editing PEG grammar files" t)
+;;
+;; You may also want something like:
+;;
+;; (setq auto-mode-alist
+;;       (append '(("\\.peg$"    . peg-mode))
+;;               auto-mode-alist))
+
+;;
+
+;;; Code:
+(defconst peg-version "0"
+  "`peg-mode' version number.")
+
+(require 'custom)
+
+(defgroup peg nil
+  "Support for editing PEG grammar files."
+  :group 'languages)
+
+(defcustom peg-mode-hook nil
+  "*Hook to be run when `peg-mode' is entered."
+  :type 'hook
+  :group 'peg)
+
+
+;; Non-customizable
+(defconst peg-comment-re "#"
+  "Regexp that starts a comment line.")
+
+
+;; Utils
+
+
+;; code
+
+
+;; major-mode stuff
+(defvar peg-mode-abbrev-table nil
+  "Abbreviation table used in `peg-mode' buffers.")
+(define-abbrev-table 'peg-mode-abbrev-table ())
+
+(defvar peg-mode-syntax-table nil
+  "Syntax table used in `peg-mode' buffers.")
+(if peg-mode-syntax-table
+    nil
+  (setq peg-mode-syntax-table (make-syntax-table)))
+;; comments: starting at ', ending at end of line
+(modify-syntax-entry ?#  "<"   peg-mode-syntax-table)
+(modify-syntax-entry ?\n ">"   peg-mode-syntax-table)
+;;  quoted strings
+(modify-syntax-entry ?\' "\""  peg-mode-syntax-table)
+(modify-syntax-entry ?\" "\""  peg-mode-syntax-table)
+;; operators
+(modify-syntax-entry ?&  "."  peg-mode-syntax-table)
+(modify-syntax-entry ?!  "."  peg-mode-syntax-table)
+(modify-syntax-entry ?+  "."  peg-mode-syntax-table)
+(modify-syntax-entry ?*  "."  peg-mode-syntax-table)
+(modify-syntax-entry ?/  "."  peg-mode-syntax-table)
+(modify-syntax-entry ?{  "<"  peg-mode-syntax-table)
+(modify-syntax-entry ?}  ">"  peg-mode-syntax-table)
+(modify-syntax-entry ?\\ "\\" peg-mode-syntax-table)
+;;
+(modify-syntax-entry ?(  "()"   peg-mode-syntax-table)
+(modify-syntax-entry ?[  "|"   peg-mode-syntax-table)
+(modify-syntax-entry ?]  "|"   peg-mode-syntax-table)
+(modify-syntax-entry ?'  "|"   peg-mode-syntax-table)
+
+
+
+;;;###autoload
+(defun  peg-mode ()
+  "Major mode for editing xrdb config files"
+  (interactive)
+  (kill-all-local-variables)
+  (set-syntax-table peg-mode-syntax-table)
+  (setq major-mode 'peg-mode
+        mode-name "peg"
+        local-abbrev-table peg-mode-abbrev-table)
+  ;(use-local-map peg-mode-map)
+  (setq font-lock-defaults '(peg-font-lock-keywords))
+  ;; local variables
+  (make-local-variable 'parse-sexp-ignore-comments)
+  (make-local-variable 'comment-start-skip)
+  (make-local-variable 'comment-start)
+  (make-local-variable 'comment-end)
+  (make-local-variable 'paragraph-start)
+  (make-local-variable 'paragraph-separate)
+  (make-local-variable 'paragraph-ignore-fill-prefix)
+  (make-local-variable 'indent-region-function)
+  ;; now set their values
+  (setq parse-sexp-ignore-comments t
+        comment-start-skip "![ \t]*"
+	comment-start "! "
+        comment-end "")
+  (setq indent-region-function 'peg-indent-region
+        paragraph-ignore-fill-prefix t
+        paragraph-start (concat "^[ \t]*$\\|^[ \t]*[!]\\|" page-delimiter)
+        paragraph-separate paragraph-start)
+  (run-hooks 'peg-mode-hook))
+
+;; faces and font-locking
+(defvar peg-rule-name-face 'peg-rule-name-face
+  "Face for a production of a PEG rule's production in a peg grammar file.")
+
+
+(make-face 'peg-rule-name-face)
+;(make-face 'xrdb-option-value-face)
+
+(defun peg-font-lock-mode-hook ()
+  (or (face-differs-from-default-p 'peg-rule-name-face)
+      (copy-face 'font-lock-keyword-face 'peg-rule-name-face))
+  (remove-hook 'font-lock-mode-hook 'peg-font-lock-mode-hook))
+(add-hook 'font-lock-mode-hook 'peg-font-lock-mode-hook)
+
+(defvar peg-font-lock-keywords
+  (list '("\\([^ \t\n]+\\)[ \t]*<-"
+          (1 peg-rule-name-face))
+	)
+  "Additional expressions to highlight in peg grammar file mode.")
+(put 'peg-mode 'font-lock-defaults '(peg-font-lock-keywords))
+
+
+(provide 'peg-mode)
+;;; peg-mode.el ends here