First sort-of-working run of urweb-mode

1 files changed, 665 insertions, 0 deletions

diff --git a/src/elisp/urweb-mode.el b/src/elisp/urweb-mode.el
new file mode 100644
index 00000000..d9e36665
--- /dev/null
+++ b/src/elisp/urweb-mode.el
@@ -0,0 +1,665 @@
+;;; urweb-mode.el --- Major mode for editing (Standard) ML
+
+;; Based on sml-mode:
+;; Copyright (C) 1999,2000,2004  Stefan Monnier
+;; Copyright (C) 1994-1997  Matthew J. Morley
+;; Copyright (C) 1989       Lars Bo Nielsen
+;;
+;; Modified for urweb-mode:
+;; Copyright (C) 2008  Adam Chlipala <adamc@hcoop.net>
+
+;; Author: Lars Bo Nielsen
+;;      Olin Shivers
+;;	Fritz Knabe (?)
+;;	Steven Gilmore (?)
+;;	Matthew Morley <mjm@scs.leeds.ac.uk> (aka <matthew@verisity.com>)
+;;	Matthias Blume <blume@cs.princeton.edu> (aka <blume@kurims.kyoto-u.ac.jp>)
+;;      (Stefan Monnier) monnier@cs.yale.edu
+;;      Adam Chlipala
+
+;; This file is not part of GNU Emacs, but it is distributed under the
+;; same conditions.
+
+;; 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 2, 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 GNU Emacs; see the file COPYING. If not, write to the
+;; Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
+
+;;; Commentary:
+
+;;; HISTORY
+
+;; Still under construction: History obscure, needs a biographer as
+;; well as a M-x doctor. Change Log on request.
+
+;; Hacked by Olin Shivers for comint from Lars Bo Nielsen's urweb.el.
+
+;; Hacked by Matthew Morley to incorporate Fritz Knabe's hilite and
+;; font-lock patterns, some of Steven Gilmore's (reduced) easy-menus,
+;; and numerous bugs and bug-fixes.
+
+;;; DESCRIPTION
+
+;; See accompanying info file: urweb-mode.info
+
+;;; FOR YOUR .EMACS FILE
+
+;; If urweb-mode.el lives in some non-standard directory, you must tell
+;; emacs where to get it. This may or may not be necessary:
+
+;; (add-to-list 'load-path "~jones/lib/emacs/")
+
+;; Then to access the commands autoload urweb-mode with that command:
+
+;; (load "urweb-mode-startup")
+
+;; urweb-mode-hook is run whenever a new urweb-mode buffer is created.
+
+;;; Code:
+
+(eval-when-compile (require 'cl))
+(require 'urweb-util)
+(require 'urweb-move)
+(require 'urweb-defs)
+(condition-case nil (require 'skeleton) (error nil))
+
+;;; VARIABLES CONTROLLING INDENTATION
+
+(defcustom urweb-indent-level 4
+  "*Indentation of blocks in Ur/Web (see also `urweb-structure-indent')."
+  :group 'urweb
+  :type '(integer))
+
+(defcustom urweb-indent-args urweb-indent-level
+  "*Indentation of args placed on a separate line."
+  :group 'urweb
+  :type '(integer))
+
+(defcustom urweb-electric-semi-mode nil
+  "*If non-nil, `\;' will self insert, reindent the line, and do a newline.
+If nil, just insert a `\;'.  (To insert while t, do: \\[quoted-insert] \;)."
+  :group 'urweb
+  :type 'boolean)
+
+(defcustom urweb-rightalign-and t
+  "If non-nil, right-align `and' with its leader.
+If nil:					If t:
+	datatype a = A				datatype a = A
+	and b = B				     and b = B"
+  :group 'urweb
+  :type 'boolean)
+
+;;; OTHER GENERIC MODE VARIABLES
+
+(defvar urweb-mode-info "urweb-mode"
+  "*Where to find Info file for `urweb-mode'.
+The default assumes the info file \"urweb-mode.info\" is on Emacs' info
+directory path.  If it is not, either put the file on the standard path
+or set the variable `urweb-mode-info' to the exact location of this file
+
+  (setq urweb-mode-info \"/usr/me/lib/info/urweb-mode\")
+
+in your .emacs file. You can always set it interactively with the
+set-variable command.")
+
+(defvar urweb-mode-hook nil
+  "*Run upon entering `urweb-mode'.
+This is a good place to put your preferred key bindings.")
+
+;;; CODE FOR Ur/Web-MODE
+
+(defun urweb-mode-info ()
+  "Command to access the TeXinfo documentation for `urweb-mode'.
+See doc for the variable `urweb-mode-info'."
+  (interactive)
+  (require 'info)
+  (condition-case nil
+      (info urweb-mode-info)
+    (error (progn
+             (describe-variable 'urweb-mode-info)
+             (message "Can't find it... set this variable first!")))))
+
+
+;; font-lock setup
+
+(defconst urweb-keywords-regexp
+  (urweb-syms-re "and" "case" "class" "con" "constraint" "constraints"
+	       "datatype" "else" "end" "extern" "fn" "fold"
+	       "fun" "functor" "if" "include"
+	       "of" "open"
+	       "rec" "sequence" "sig" "signature"
+	       "struct" "structure" "table" "then" "type" "val" "where"
+	       "with"
+
+               "Name" "Type" "Unit")
+  "A regexp that matches any non-SQL keywords of Ur/Web.")
+
+(defconst urweb-sql-keywords-regexp
+  (urweb-syms-re "SELECT" "FROM" "AS" "WHERE" "SQL" "GROUP" "ORDER" "BY"
+                 "HAVING" "LIMIT" "OFFSET" "ALL" "UNION" "INTERSECT" "EXCEPT"
+                 "TRUE" "FALSE" "AND" "OR" "NOT" "COUNT" "AVG" "SUM" "MIN" "MAX"
+                 "ASC" "DESC" "INSERT" "INTO" "VALUES" "UPDATE" "SET" "DELETE")
+  "A regexp that matches SQL keywords.")
+
+;;; Font-lock settings ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+
+;; The font lock regular expressions.
+
+(defconst urweb-font-lock-keywords
+  `(;;(urweb-font-comments-and-strings)
+    (,(concat "\\<\\(fun\\|and\\)\\s-+\\(\\sw+\\)\\s-+[^ \t\n=]")
+     (1 font-lock-keyword-face)
+     (6 font-lock-function-name-face))
+    (,(concat "\\<\\(\\(data\\)?type\\|con\\)\\s-+\\(\\sw+\\)")
+     (1 font-lock-keyword-face)
+     (7 font-lock-type-def-face))
+    ("\\<\\(val\\)\\s-+\\(\\sw+\\>\\s-*\\)?\\(\\sw+\\)\\s-*[=:]"
+     (1 font-lock-keyword-face)
+     (3 font-lock-variable-name-face))
+    ("\\<\\(structure\\|functor\\)\\s-+\\(\\sw+\\)"
+     (1 font-lock-keyword-face)
+     (2 font-lock-module-def-face))
+    ("\\<\\(signature\\)\\s-+\\(\\sw+\\)"
+     (1 font-lock-keyword-face)
+     (2 font-lock-interface-def-face))
+    
+    (,urweb-keywords-regexp . font-lock-keyword-face)
+    (,urweb-sql-keywords-regexp . font-lock-sql-face))
+  "Regexps matching standard Ur/Web keywords.")
+
+(defface font-lock-type-def-face
+  '((t (:bold t)))
+  "Font Lock mode face used to highlight type definitions."
+  :group 'font-lock-highlighting-faces)
+(defvar font-lock-type-def-face 'font-lock-type-def-face
+  "Face name to use for type definitions.")
+
+(defface font-lock-module-def-face
+  '((t (:bold t)))
+  "Font Lock mode face used to highlight module definitions."
+  :group 'font-lock-highlighting-faces)
+(defvar font-lock-module-def-face 'font-lock-module-def-face
+  "Face name to use for module definitions.")
+
+(defface font-lock-interface-def-face
+  '((t (:bold t)))
+  "Font Lock mode face used to highlight interface definitions."
+  :group 'font-lock-highlighting-faces)
+(defvar font-lock-interface-def-face 'font-lock-interface-def-face
+  "Face name to use for interface definitions.")
+
+(defface font-lock-sql-face
+  '((t (:bold t)))
+  "Font Lock mode face used to highlight SQL keywords."
+  :group 'font-lock-highlighting-faces)
+(defvar font-lock-sql-face 'font-lock-sql-face
+  "Face name to use for SQL keywords.")
+
+;;
+;; Code to handle nested comments and unusual string escape sequences
+;;
+
+(defsyntax urweb-syntax-prop-table
+  '((?\\ . ".") (?* . "."))
+  "Syntax table for text-properties")
+
+;; For Emacsen that have no built-in support for nested comments
+(defun urweb-get-depth-st ()
+  (save-excursion
+    (let* ((disp (if (eq (char-before) ?\)) (progn (backward-char) -1) nil))
+	   (_ (backward-char))
+	   (disp (if (eq (char-before) ?\() (progn (backward-char) 0) disp))
+	   (pt (point)))
+      (when disp
+	(let* ((depth
+		(save-match-data
+		  (if (re-search-backward "\\*)\\|(\\*" nil t)
+		      (+ (or (get-char-property (point) 'comment-depth) 0)
+			 (case (char-after) (?\( 1) (?* 0))
+			 disp)
+		    0)))
+	       (depth (if (> depth 0) depth)))
+	  (put-text-property pt (1+ pt) 'comment-depth depth)
+	  (when depth urweb-syntax-prop-table))))))
+
+(defconst urweb-font-lock-syntactic-keywords
+  `(("^\\s-*\\(\\\\\\)" (1 ',urweb-syntax-prop-table))
+    ,@(unless urweb-builtin-nested-comments-flag
+	'(("(?\\(\\*\\))?" (1 (urweb-get-depth-st)))))))
+
+(defconst urweb-font-lock-defaults
+  '(urweb-font-lock-keywords nil nil ((?_ . "w") (?' . "w")) nil
+    (font-lock-syntactic-keywords . urweb-font-lock-syntactic-keywords)))
+
+;;;;
+;;;; Imenu support
+;;;;
+
+(defvar urweb-imenu-regexp
+  (concat "^[ \t]*\\(let[ \t]+\\)?"
+	  (regexp-opt (append urweb-module-head-syms
+			      '("and" "fun" "datatype" "type")) t)
+	  "\\>"))
+
+(defun urweb-imenu-create-index ()
+  (let (alist)
+    (goto-char (point-max))
+    (while (re-search-backward urweb-imenu-regexp nil t)
+      (save-excursion
+	(let ((kind (match-string 2))
+	      (column (progn (goto-char (match-beginning 2)) (current-column)))
+	      (location
+	       (progn (goto-char (match-end 0))
+		      (urweb-forward-spaces)
+		      (when (looking-at urweb-tyvarseq-re)
+			(goto-char (match-end 0)))
+		      (point)))
+	      (name (urweb-forward-sym)))
+	  ;; Eliminate trivial renamings.
+	  (when (or (not (member kind '("structure" "signature")))
+		    (progn (search-forward "=")
+			   (urweb-forward-spaces)
+			   (looking-at "sig\\|struct")))
+	    (push (cons (concat (make-string (/ column 2) ?\ ) name) location)
+		  alist)))))
+    alist))
+
+;;; MORE CODE FOR URWEB-MODE
+
+;;;###autoload (add-to-list 'load-path (file-name-directory load-file-name))
+;;;###autoload
+(add-to-list 'auto-mode-alist '("\\.s\\(ml\\|ig\\)\\'" . urweb-mode))
+
+;;;###autoload
+(define-derived-mode urweb-mode fundamental-mode "Ur/Web"
+  "\\<urweb-mode-map>Major mode for editing Ur/Web code.
+This mode runs `urweb-mode-hook' just before exiting.
+\\{urweb-mode-map}"
+  (set (make-local-variable 'font-lock-defaults) urweb-font-lock-defaults)
+  (set (make-local-variable 'outline-regexp) urweb-outline-regexp)
+  (set (make-local-variable 'imenu-create-index-function)
+       'urweb-imenu-create-index)
+  (set (make-local-variable 'add-log-current-defun-function)
+       'urweb-current-fun-name)
+  ;; Treat paragraph-separators in comments as paragraph-separators.
+  (set (make-local-variable 'paragraph-separate)
+       (concat "\\([ \t]*\\*)?\\)?\\(" paragraph-separate "\\)"))
+  (set (make-local-variable 'require-final-newline) t)
+  ;; forward-sexp-function is an experimental variable in my hacked Emacs.
+  (set (make-local-variable 'forward-sexp-function) 'urweb-user-forward-sexp)
+  ;; For XEmacs
+  (easy-menu-add urweb-mode-menu)
+  ;; Compatibility.  FIXME: we should use `-' in Emacs-CVS.
+  (unless (boundp 'skeleton-positions) (set (make-local-variable '@) nil))
+  (urweb-mode-variables))
+
+(defun urweb-mode-variables ()
+  (set-syntax-table urweb-mode-syntax-table)
+  (setq local-abbrev-table urweb-mode-abbrev-table)
+  ;; A paragraph is separated by blank lines or ^L only.
+  
+  (set (make-local-variable 'indent-line-function) 'urweb-indent-line)
+  (set (make-local-variable 'comment-start) "(* ")
+  (set (make-local-variable 'comment-end) " *)")
+  (set (make-local-variable 'comment-nested) t)
+  ;;(set (make-local-variable 'block-comment-start) "* ")
+  ;;(set (make-local-variable 'block-comment-end) "")
+  ;; (set (make-local-variable 'comment-column) 40)
+  (set (make-local-variable 'comment-start-skip) "(\\*+\\s-*"))
+
+(defun urweb-funname-of-and ()
+  "Name of the function this `and' defines, or nil if not a function.
+Point has to be right after the `and' symbol and is not preserved."
+  (urweb-forward-spaces)
+  (if (looking-at urweb-tyvarseq-re) (goto-char (match-end 0)))
+  (let ((sym (urweb-forward-sym)))
+    (urweb-forward-spaces)
+    (unless (or (member sym '(nil "d="))
+		(member (urweb-forward-sym) '("d=")))
+      sym)))
+
+;;; INDENTATION !!!
+
+(defun urweb-mark-function ()
+  "Synonym for `mark-paragraph' -- sorry.
+If anyone has a good algorithm for this..."
+  (interactive)
+  (mark-paragraph))
+
+(defun urweb-indent-line ()
+  "Indent current line of Ur/Web code."
+  (interactive)
+  (let ((savep (> (current-column) (current-indentation)))
+	(indent (max (or (ignore-errors (urweb-calculate-indentation)) 0) 0)))
+    (if savep
+	(save-excursion (indent-line-to indent))
+      (indent-line-to indent))))
+
+(defun urweb-back-to-outer-indent ()
+  "Unindents to the next outer level of indentation."
+  (interactive)
+  (save-excursion
+    (beginning-of-line)
+    (skip-chars-forward "\t ")
+    (let ((start-column (current-column))
+          (indent (current-column)))
+      (if (> start-column 0)
+          (progn
+            (save-excursion
+              (while (>= indent start-column)
+                (if (re-search-backward "^[^\n]" nil t)
+                    (setq indent (current-indentation))
+                  (setq indent 0))))
+            (backward-delete-char-untabify (- start-column indent)))))))
+
+(defun urweb-find-comment-indent ()
+  (save-excursion
+    (let ((depth 1))
+      (while (> depth 0)
+	(if (re-search-backward "(\\*\\|\\*)" nil t)
+	    (cond
+	     ;; FIXME: That's just a stop-gap.
+	     ((eq (get-text-property (point) 'face) 'font-lock-string-face))
+	     ((looking-at "*)") (incf depth))
+	     ((looking-at comment-start-skip) (decf depth)))
+	  (setq depth -1)))
+      (if (= depth 0)
+	  (1+ (current-column))
+	nil))))
+
+(defun urweb-calculate-indentation ()
+  (save-excursion
+    (beginning-of-line) (skip-chars-forward "\t ")
+    (urweb-with-ist
+     ;; Indentation for comments alone on a line, matches the
+     ;; proper indentation of the next line.
+     (when (looking-at "(\\*") (urweb-forward-spaces))
+     (let (data
+	   (sym (save-excursion (urweb-forward-sym))))
+       (or
+	;; Allow the user to override the indentation.
+	(when (looking-at (concat ".*" (regexp-quote comment-start)
+				  "[ \t]*fixindent[ \t]*"
+				  (regexp-quote comment-end)))
+	  (current-indentation))
+
+	;; Continued comment.
+	(and (looking-at "\\*") (urweb-find-comment-indent))
+
+	;; Continued string ? (Added 890113 lbn)
+	(and (looking-at "\\\\")
+	     (save-excursion
+	       (if (save-excursion (previous-line 1)
+				   (beginning-of-line)
+				   (looking-at "[\t ]*\\\\"))
+		   (progn (previous-line 1) (current-indentation))
+		 (if (re-search-backward "[^\\\\]\"" nil t)
+		     (1+ (current-column))
+		   0))))
+
+	;; Closing parens.  Could be handled below with `urweb-indent-relative'?
+	(and (looking-at "\\s)")
+	     (save-excursion
+	       (skip-syntax-forward ")")
+	       (backward-sexp 1)
+	       (if (urweb-dangling-sym)
+		   (urweb-indent-default 'noindent)
+		 (current-column))))
+
+	(and (setq data (assoc sym urweb-close-paren))
+	     (urweb-indent-relative sym data))
+
+	(and (member sym urweb-starters-syms)
+	     (urweb-indent-starter sym))
+
+	(and (string= sym "|") (urweb-indent-pipe))
+
+	(urweb-indent-arg)
+	(urweb-indent-default))))))
+
+(defsubst urweb-bolp ()
+  (save-excursion (skip-chars-backward " \t|") (bolp)))
+
+(defun urweb-indent-starter (orig-sym)
+  "Return the indentation to use for a symbol in `urweb-starters-syms'.
+Point should be just before the symbol ORIG-SYM and is not preserved."
+  (let ((sym (unless (save-excursion (urweb-backward-arg))
+	       (urweb-backward-spaces)
+	       (urweb-backward-sym))))
+    (if (member sym '(";" "d=")) (setq sym nil))
+    (if sym (urweb-get-sym-indent sym)
+      ;; FIXME: this can take a *long* time !!
+      (setq sym (urweb-find-matching-starter urweb-starters-syms))
+      ;; Don't align with `and' because it might be specially indented.
+      (if (and (or (equal orig-sym "and") (not (equal sym "and")))
+	       (urweb-bolp))
+	  (+ (current-column)
+	     (if (and urweb-rightalign-and (equal orig-sym "and"))
+		 (- (length sym) 3) 0))
+	(urweb-indent-starter orig-sym)))))
+
+(defun urweb-indent-relative (sym data)
+  (save-excursion
+    (urweb-forward-sym) (urweb-backward-sexp nil)
+    (unless (second data) (urweb-backward-spaces) (urweb-backward-sym))
+    (+ (or (cdr (assoc sym urweb-symbol-indent)) 0)
+       (urweb-delegated-indent))))
+
+(defun urweb-indent-pipe ()
+  (let ((sym (urweb-find-matching-starter urweb-pipeheads
+					(urweb-op-prec "|" 'back))))
+    (when sym
+      (if (string= sym "|")
+	  (if (urweb-bolp) (current-column) (urweb-indent-pipe))
+	(let ((pipe-indent (or (cdr (assoc "|" urweb-symbol-indent)) -2)))
+	  (when (or (member sym '("datatype"))
+		    (and (equal sym "and")
+			 (save-excursion
+			   (forward-word 1)
+			   (not (urweb-funname-of-and)))))
+	    (re-search-forward "="))
+	  (urweb-forward-sym)
+	  (urweb-forward-spaces)
+	  (+ pipe-indent (current-column)))))))
+
+(defun urweb-find-forward (re)
+  (urweb-forward-spaces)
+  (while (and (not (looking-at re))
+	      (progn
+		(or (ignore-errors (forward-sexp 1) t) (forward-char 1))
+		(urweb-forward-spaces)
+		(not (looking-at re))))))
+
+(defun urweb-indent-arg ()
+  (and (save-excursion (ignore-errors (urweb-forward-arg)))
+       ;;(not (looking-at urweb-not-arg-re))
+       ;; looks like a function or an argument
+       (urweb-move-if (urweb-backward-arg))
+       ;; an argument
+       (if (save-excursion (not (urweb-backward-arg)))
+	   ;; a first argument
+	   (+ (current-column) urweb-indent-args)
+	 ;; not a first arg
+	 (while (and (/= (current-column) (current-indentation))
+		     (urweb-move-if (urweb-backward-arg))))
+	 (unless (save-excursion (urweb-backward-arg))
+	   ;; all earlier args are on the same line
+	   (urweb-forward-arg) (urweb-forward-spaces))
+	 (current-column))))
+
+(defun urweb-get-indent (data sym)
+  (let (d)
+    (cond
+     ((not (listp data)) data)
+     ((setq d (member sym data)) (cadr d))
+     ((and (consp data) (not (stringp (car data)))) (car data))
+     (t urweb-indent-level))))
+
+(defun urweb-dangling-sym ()
+  "Non-nil if the symbol after point is dangling.
+The symbol can be an Ur/Web symbol or an open-paren. \"Dangling\" means that
+it is not on its own line but is the last element on that line."
+  (save-excursion
+    (and (not (urweb-bolp))
+	 (< (urweb-point-after (end-of-line))
+	    (urweb-point-after (or (urweb-forward-sym) (skip-syntax-forward "("))
+			     (urweb-forward-spaces))))))
+
+(defun urweb-delegated-indent ()
+  (if (urweb-dangling-sym)
+      (urweb-indent-default 'noindent)
+    (urweb-move-if (backward-word 1)
+		 (looking-at urweb-agglomerate-re))
+    (current-column)))
+
+(defun urweb-get-sym-indent (sym &optional style)
+  "Find the indentation for the SYM we're `looking-at'.
+If indentation is delegated, point will move to the start of the parent.
+Optional argument STYLE is currently ignored."
+  (assert (equal sym (save-excursion (urweb-forward-sym))))
+  (save-excursion
+    (let ((delegate (and (not (equal sym "end")) (assoc sym urweb-close-paren)))
+	  (head-sym sym))
+      (when (and delegate (not (eval (third delegate))))
+	;;(urweb-find-match-backward sym delegate)
+	(urweb-forward-sym) (urweb-backward-sexp nil)
+	(setq head-sym
+	      (if (second delegate)
+		  (save-excursion (urweb-forward-sym))
+		(urweb-backward-spaces) (urweb-backward-sym))))
+
+      (let ((idata (assoc head-sym urweb-indent-rule)))
+	(when idata
+	  ;;(if (or style (not delegate))
+	  ;; normal indentation
+	  (let ((indent (urweb-get-indent (cdr idata) sym)))
+	    (when indent (+ (urweb-delegated-indent) indent)))
+	  ;; delgate indentation to the parent
+	  ;;(urweb-forward-sym) (urweb-backward-sexp nil)
+	  ;;(let* ((parent-sym (save-excursion (urweb-forward-sym)))
+	  ;;     (parent-indent (cdr (assoc parent-sym urweb-indent-starters))))
+	  ;; check the special rules
+	  ;;(+ (urweb-delegated-indent)
+	  ;; (or (urweb-get-indent (cdr indent-data) 1 'strict)
+	  ;; (urweb-get-indent (cdr parent-indent) 1 'strict)
+	  ;; (urweb-get-indent (cdr indent-data) 0)
+	  ;; (urweb-get-indent (cdr parent-indent) 0))))))))
+	  )))))
+
+(defun urweb-indent-default (&optional noindent)
+  (let* ((sym-after (save-excursion (urweb-forward-sym)))
+	 (_ (urweb-backward-spaces))
+	 (sym-before (urweb-backward-sym))
+	 (sym-indent (and sym-before (urweb-get-sym-indent sym-before)))
+	 (indent-after (or (cdr (assoc sym-after urweb-symbol-indent)) 0)))
+    (when (equal sym-before "end")
+      ;; I don't understand what's really happening here, but when
+      ;; it's `end' clearly, we need to do something special.
+      (forward-word 1)
+      (setq sym-before nil sym-indent nil))
+    (cond
+     (sym-indent
+      ;; the previous sym is an indentation introducer: follow the rule
+      (if noindent
+	  ;;(current-column)
+	  sym-indent
+	(+ sym-indent indent-after)))
+     ;; If we're just after a hanging open paren.
+     ((and (eq (char-syntax (preceding-char)) ?\()
+	   (save-excursion (backward-char) (urweb-dangling-sym)))
+      (backward-char)
+      (urweb-indent-default))
+     (t
+      ;; default-default
+      (let* ((prec-after (urweb-op-prec sym-after 'back))
+	     (prec (or (urweb-op-prec sym-before 'back) prec-after 100)))
+	;; go back until you hit a symbol that has a lower prec than the
+	;; "current one", or until you backed over a sym that has the same prec
+	;; but is at the beginning of a line.
+	(while (and (not (urweb-bolp))
+		    (while (urweb-move-if (urweb-backward-sexp (1- prec))))
+		    (not (urweb-bolp)))
+	  (while (urweb-move-if (urweb-backward-sexp prec))))
+	(if noindent
+	    ;; the `noindent' case does back over an introductory symbol
+	    ;; such as `fun', ...
+	    (progn
+	      (urweb-move-if
+	       (urweb-backward-spaces)
+	       (member (urweb-backward-sym) urweb-starters-syms))
+	      (current-column))
+	  ;; Use `indent-after' for cases such as when , or ; should be
+	  ;; outdented so that their following terms are aligned.
+	  (+ (if (progn
+		   (if (equal sym-after ";")
+		       (urweb-move-if
+			(urweb-backward-spaces)
+			(member (urweb-backward-sym) urweb-starters-syms)))
+		   (and sym-after (not (looking-at sym-after))))
+		 indent-after 0)
+	     (current-column))))))))
+
+
+;; maybe `|' should be set to word-syntax in our temp syntax table ?
+(defun urweb-current-indentation ()
+  (save-excursion
+    (beginning-of-line)
+    (skip-chars-forward " \t|")
+    (current-column)))
+
+
+(defun urweb-find-matching-starter (syms &optional prec)
+  (let (sym)
+    (ignore-errors
+      (while
+	  (progn (urweb-backward-sexp prec)
+		 (setq sym (save-excursion (urweb-forward-sym)))
+		 (not (or (member sym syms) (bobp)))))
+      (if (member sym syms) sym))))
+
+(defun urweb-skip-siblings ()
+  (while (and (not (bobp)) (urweb-backward-arg))
+    (urweb-find-matching-starter urweb-starters-syms)))
+
+(defun urweb-beginning-of-defun ()
+  (let ((sym (urweb-find-matching-starter urweb-starters-syms)))
+    (if (member sym '("fun" "and" "functor" "signature" "structure"
+		      "datatype"))
+	(save-excursion (urweb-forward-sym) (urweb-forward-spaces)
+			(urweb-forward-sym))
+      ;; We're inside a "non function declaration": let's skip all other
+      ;; declarations that we find at the same level and try again.
+      (urweb-skip-siblings)
+      ;; Obviously, let's not try again if we're at bobp.
+      (unless (bobp) (urweb-beginning-of-defun)))))
+
+(defcustom urweb-max-name-components 3
+  "Maximum number of components to use for the current function name."
+  :group 'urweb
+  :type 'integer)
+
+(defun urweb-current-fun-name ()
+  (save-excursion
+    (let ((count urweb-max-name-components)
+	  fullname name)
+      (end-of-line)
+      (while (and (> count 0)
+		  (setq name (urweb-beginning-of-defun)))
+	(decf count)
+	(setq fullname (if fullname (concat name "." fullname) name))
+	;; Skip all other declarations that we find at the same level.
+	(urweb-skip-siblings))
+      fullname)))
+
+(provide 'urweb-mode)
+
+;;; urweb-mode.el ends here