diff --git a/tools/hept-mode.el b/tools/hept-mode.el
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+;;; hept-mode.el --- major mode for Heptagon files
+
+;; Copyright (C) 1999, 2000, 2001 Free Software Foundation, Inc.
+;;
+;; Author: adrien.guatto@ens.fr
+;; Keywords: languages
+;; Version: 1.0
+;; X-URL: http://heptagon.gforge.inria.fr
+
+;; This file is not part of GNU Emacs.
+
+;;; Commentary:
+
+;; Major mode for editing Heptagon files, usually files ending
+;; with `.ept' and `.epi'.
+
+;; This package provides the following features:
+;;  * Syntax coloring (via font-lock) for grammar symbols and
+;;    builtin functions and variables
+;;  * Indentation for the current line (TAB) and selected region (C-M-\).
+;;  * Switching between file.vert and file.frag
+;;    with S-lefttab (via ff-find-other-file)
+
+;;; Installation:
+
+;; If hept-mode is not part of your distribution, put this file into your
+;; load-path and the following into your ~/.emacs:
+;;   (autoload 'hept-mode "hept-mode" nil t)
+;;   (add-to-list 'auto-mode-alist '("\\.ept\\'" . hept-mode))
+;;   (add-to-list 'auto-mode-alist '("\\.epi\\'" . hept-mode))
+
+;; To customize, use `M-x customize-group RET antlr RET' or the custom browser
+;; (Emacs->Programming->Languages->Antlr).
+
+;;; Code:
+
+(provide 'hept-mode)
+
+(eval-when-compile
+  (require 'find-file))
+
+(defconst hept-version "1.0"
+  "Heptagon major mode version number.")
+
+(defvar hept-mode-hook nil)
+
+(defvar hept-mode-map
+  (let ((hept-mode-map (make-sparse-keymap)))
+    (define-key hept-mode-map [S-iso-lefttab] 'ff-find-other-file)
+    hept-mode-map)
+  "Keymap for Heptagon major mode")
+
+(add-to-list 'auto-mode-alist '("\\.ept\\'" . hept-mode))
+(add-to-list 'auto-mode-alist '("\\.ept\\'" . hept-mode))
+
+;; (regexp-opt '(
+;;             "fun" "node" "returns" "open" "inlined" "let" "tel" "var" "const"
+;;               )
+;;             t)
+
+;; (regexp-opt '(
+;;               "bool" "int" "float"
+;;               )
+;;             t)
+
+;; (regexp-opt '(
+;;               "with" "merge" "when" "whenot"
+;;               "fby" "pre" "on" "end" "automaton" "state"
+;;               "switch" "every" "reset" "until" "unless"
+;;               "last" "if" "then" "else" "default" "do" "done" "in" "continue"
+;;               "contract" "assume" "enforce" "with"
+;;               "map" "fold" "mapfold" "mapi" "foldi" "mapfoldi"
+;;               )
+;;             t)
+
+(defconst hept-font-lock-keywords-1
+  (list
+   '(
+     "\\<\\(const\\|fun\\|inlined\\|let\\|node\\|open\\|returns\\|tel\\|var\\)\\>"
+     .
+     font-lock-variable-name-face)
+   '("\\<\\(bool\\|\\(?:floa\\|in\\)t\\)\\>"
+     .
+     font-lock-builtin-face)
+   '(
+     "\\<\\(a\\(?:ssume\\|utomaton\\)\\|cont\\(?:inue\\|ract\\)\\|d\\(?:efault\\|o\\(?:ne\\)?\\)\\|e\\(?:lse\\|n\\(?:d\\|force\\)\\|very\\)\\|f\\(?:by\\|oldi?\\)\\|i[fn]\\|last\\|m\\(?:ap\\(?:foldi?\\|i\\)?\\|erge\\)\\|on\\|pre\\|reset\\|s\\(?:tate\\|witch\\)\\|then\\|un\\(?:less\\|til\\)\\|w\\(?:hen\\(?:ot\\)?\\|ith\\)\\)\\>"
+     .
+     font-lock-keyword-face)
+   )
+  "Minimal highlighting expressions for Heptagon mode")
+
+(defvar hept-font-lock-keywords hept-font-lock-keywords-1
+  "Default highlighting expressions for Heptagon mode")
+
+(defvar hept-mode-syntax-table
+  (let ((hept-mode-syntax-table (make-syntax-table)))
+    (modify-syntax-entry ?( "()1n" hept-mode-syntax-table)
+    (modify-syntax-entry ?) ")(4n" hept-mode-syntax-table)
+    (modify-syntax-entry ?* ". 23" hept-mode-syntax-table)
+    (modify-syntax-entry ?< "(>" hept-mode-syntax-table)
+    (modify-syntax-entry ?> ")<" hept-mode-syntax-table)
+    (modify-syntax-entry ?\ "\\" hept-mode-syntax-table)
+    (modify-syntax-entry ?_ "_" hept-mode-syntax-table)
+    (modify-syntax-entry ?: "." hept-mode-syntax-table)
+;    (modify-syntax-entry ?\n "> b" hept-mode-syntax-table)
+    hept-mode-syntax-table)
+  "Syntax table for hept-mode")
+
+(defun hept-indent-line ()
+  "Indent current line as Heptagon code"
+  (interactive)
+  (if (bobp)
+      (indent-line-to 0)
+    (let ((not-indented t) cur-indent)
+      (save-excursion
+        (while not-indented
+          (forward-line -1)
+          (if (looking-at "^[ \t]*\\(tel\\|end\\|done\\)")
+              (progn
+                (setq cur-indent (current-indentation))
+                (setq not-indented nil))
+                                        ; Check for rule 4
+            (if (looking-at
+                 "^[ \t]*\\(let\\|automaton\\)")
+                (progn
+                  (setq cur-indent (+ (current-indentation) default-tab-width))
+                  (setq not-indented nil))
+              (if (looking-at "^[ \t]*\\(do\\)")
+                  (progn
+                    (setq cur-indent (+ (current-indentation) 3))
+                    (setq not-indented nil))
+                (if (bobp) ; Check for rule 5
+                    (setq not-indented nil)))))))
+      (if cur-indent
+          (indent-line-to cur-indent)
+        (indent-line-to 0)))))
+
+(defvar hept-other-file-alist
+  '(("\\.ept$" (".epi"))
+    ("\\.epi$" (".ept")))
+  "Alist of extensions to find given the current file's extension")
+
+(define-derived-mode hept-mode fundamental-mode "Heptagon"
+  "Major mode for editing Heptagon files."
+  :syntax-table hept-mode-syntax-table
+  (set (make-local-variable 'comment-start) "(*")
+  (set (make-local-variable 'comment-end) "*)")
+  (set (make-local-variable 'indent-line-function) 'hept-indent-line)
+  (set (make-local-variable 'font-lock-defaults) '(hept-font-lock-keywords))
+  (set (make-local-variable 'ff-other-file-alist) 'hept-other-file-alist)
+  )
+
+;;; hept-mode.el ends here
\ No newline at end of file