;;; fortran.el --- Fortran mode for GNU Emacs

;; Copyright (c) 1986, 1993, 1994, 1995, 1997, 1998 Free Software Foundation, Inc.

;; Author: Michael D. Prange <prange@erl.mit.edu>
;; Maintainer: Dave Love <fx@gnu.org>
;; Keywords: languages

;; This file is part of GNU Emacs.

;; GNU Emacs 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.

;; GNU Emacs 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 mode is documented in the Emacs manual.
;;
;; Note that it is for editing Fortran77 or Fortran90 fixed source
;; form.  For editing Fortran90 free format source, use `f90-mode'
;; (f90.el).

;;; History:

;; Fortran mode was upgraded by Stephen A. Wood (saw@cebaf.gov).

;; We acknowledge many contributions and valuable suggestions by
;; Lawrence R. Dodd, Ralf Fassel, Ralph Finch, Stephen Gildea,
;; Dr. Anil Gokhale, Ulrich Mueller, Mark Neale, Eric Prestemon,
;; Gary Sabot and Richard Stallman.

;;; Code:

(require 'easymenu)

(defgroup fortran nil
  "Fortran mode for Emacs"
  :group 'languages)

(defgroup fortran-indent nil
  "Indentation variables in Fortran mode"
  :prefix "fortran-"
  :group 'fortran)

(defgroup fortran-comment nil
  "Comment-handling variables in Fortran mode"
  :prefix "fortran-"
  :group 'fortran)


;;;###autoload
(defcustom fortran-tab-mode-default nil
  "*Default tabbing/carriage control style for empty files in Fortran mode.
A value of t specifies tab-digit style of continuation control.
A value of nil specifies that continuation lines are marked
with a character in column 6."
  :type 'boolean
  :group 'fortran-indent)

;; Buffer local, used to display mode line.
(defcustom fortran-tab-mode-string nil
  "String to appear in mode line when TAB format mode is on."
  :type '(choice (const nil) string)
  :group 'fortran-indent)

(defcustom fortran-do-indent 3
  "*Extra indentation applied to DO blocks."
  :type 'integer
  :group 'fortran-indent)

(defcustom fortran-if-indent 3
  "*Extra indentation applied to IF blocks."
  :type 'integer
  :group 'fortran-indent)

(defcustom fortran-structure-indent 3
  "*Extra indentation applied to STRUCTURE, UNION, MAP and INTERFACE blocks."
  :type 'integer
  :group 'fortran-indent)

(defcustom fortran-continuation-indent 5
  "*Extra indentation applied to Fortran continuation lines."
  :type 'integer
  :group 'fortran-indent)

(defcustom fortran-comment-indent-style 'fixed
  "*How to indent comments.
nil forces comment lines not to be touched,
'fixed makes fixed comment indentation to `fortran-comment-line-extra-indent'
columns beyond `fortran-minimum-statement-indent-fixed' (for
`indent-tabs-mode' of nil) or `fortran-minimum-statement-indent-tab' (for
`indent-tabs-mode' of t), and 'relative indents to current
Fortran indentation plus `fortran-comment-line-extra-indent'."
  :type '(radio (const nil) (const fixed) (const relative))
  :group 'fortran-indent)

(defcustom fortran-comment-line-extra-indent 0
  "*Amount of extra indentation for text within full-line comments."
  :type 'integer
  :group 'fortran-indent
  :group 'fortran-comment)

(defcustom comment-line-start nil
  "*Delimiter inserted to start new full-line comment."
  :type '(choice string (const nil))
  :group 'fortran-comment)

(defcustom comment-line-start-skip nil
  "*Regexp to match the start of a full-line comment."
  :type '(choice string (const nil))
  :group 'fortran-comment)

(defcustom fortran-minimum-statement-indent-fixed 6
  "*Minimum statement indentation for fixed format continuation style."
  :type 'integer
  :group 'fortran-indent)

(defcustom fortran-minimum-statement-indent-tab (max tab-width 6)
  "*Minimum statement indentation for TAB format continuation style."
  :type 'integer
  :group 'fortran-indent)

;; Note that this is documented in the v18 manuals as being a string
;; of length one rather than a single character.
;; The code in this file accepts either format for compatibility.
(defcustom fortran-comment-indent-char " "
  "*Single-character string inserted for Fortran comment indentation.
Normally a space."
  :type 'string
  :group 'fortran-comment)

(defcustom fortran-line-number-indent 1
  "*Maximum indentation for Fortran line numbers.
5 means right-justify them within their five-column field."
  :type 'integer
  :group 'fortran-indent)

(defcustom fortran-check-all-num-for-matching-do nil
  "*Non-nil causes all numbered lines to be treated as possible DO loop ends."
  :type 'boolean
  :group 'fortran)

(defcustom fortran-blink-matching-if nil
  "*Non-nil causes \\[fortran-indent-line] on ENDIF statement to blink on matching IF.
Also, from an ENDDO statement blink on matching DO [WHILE] statement."
  :type 'boolean
  :group 'fortran)

(defcustom fortran-continuation-string "$"
  "*Single-character string used for Fortran continuation lines.
In fixed format continuation style, this character is inserted in
column 6 by \\[fortran-split-line] to begin a continuation line.
Also, if \\[fortran-indent-line] finds this at the beginning of a line, it will
convert the line into a continuation line of the appropriate style.
Normally $."
  :type 'string
  :group 'fortran)

(defcustom fortran-comment-region "c$$$"
  "*String inserted by \\[fortran-comment-region]\
at start of each line in region."
  :type 'string
  :group 'fortran-comment)

(defcustom fortran-electric-line-number t
  "*Non-nil causes line number digits to be moved to the correct column as\
typed."
  :type 'boolean
  :group 'fortran)

(defcustom fortran-startup-message t
  "*Non-nil displays a startup message when Fortran mode is first called."
  :type 'boolean
  :group 'fortran)

(defvar fortran-column-ruler-fixed
  "0   4 6  10        20        30        40        5\
0        60        70\n\
\[   ]|{   |    |    |    |    |    |    |    |    \
\|    |    |    |    |}\n"
  "*String displayed above current line by \\[fortran-column-ruler].
This variable used in fixed format mode.")

(defvar fortran-column-ruler-tab
  "0       810        20        30        40        5\
0        60        70\n\
\[   ]|  { |    |    |    |    |    |    |    |    \
\|    |    |    |    |}\n"
  "*String displayed above current line by \\[fortran-column-ruler].
This variable used in TAB format mode.")

(defconst bug-fortran-mode "bug-fortran-mode@erl.mit.edu"
  "Address of mailing list for Fortran mode bugs.")

(defvar fortran-mode-syntax-table nil
  "Syntax table in use in Fortran mode buffers.")

(defvar fortran-analyze-depth 100
  "Number of lines to scan to determine whether to use fixed or TAB format\
style.")

(defcustom fortran-break-before-delimiters t
  "*Non-nil causes `fortran-fill' to break lines before delimiters."
  :type 'boolean
  :group 'fortran)

(if fortran-mode-syntax-table
    ()
  (setq fortran-mode-syntax-table (make-syntax-table))
  ;; We might like `;' to be punctuation (g77 multi-statement lines),
  ;; but that screws abbrevs.
  (modify-syntax-entry ?\; "w" fortran-mode-syntax-table)
  (modify-syntax-entry ?\r " " fortran-mode-syntax-table)
  (modify-syntax-entry ?+ "." fortran-mode-syntax-table)
  (modify-syntax-entry ?- "." fortran-mode-syntax-table)
  (modify-syntax-entry ?= "." fortran-mode-syntax-table)
  (modify-syntax-entry ?* "." fortran-mode-syntax-table)
  (modify-syntax-entry ?/ "." fortran-mode-syntax-table)
  (modify-syntax-entry ?\' "\"" fortran-mode-syntax-table)
  (modify-syntax-entry ?\" "\"" fortran-mode-syntax-table)
  (modify-syntax-entry ?\\ "/" fortran-mode-syntax-table)
  ;; This might be better as punctuation, as for C, but this way you
  ;; can treat floating-point numbers as symbols.
  (modify-syntax-entry ?. "_" fortran-mode-syntax-table) ; e.g. `a.ne.b'
  (modify-syntax-entry ?_ "_" fortran-mode-syntax-table)
  (modify-syntax-entry ?$ "_" fortran-mode-syntax-table) ; esp. VMSisms
  (modify-syntax-entry ?\! "<" fortran-mode-syntax-table)
  (modify-syntax-entry ?\n ">" fortran-mode-syntax-table))

;; Comments are real pain in Fortran because there is no way to represent the
;; standard comment syntax in an Emacs syntax table (we can for VAX-style).
;; Therefore an unmatched quote in a standard comment will throw fontification
;; off on the wrong track.  So we do syntactic fontification with regexps.

;; Regexps done by simon@gnu with help from Ulrik Dickow <dickow@nbi.dk> and
;; probably others Si's forgotten about (sorry).

(defconst fortran-font-lock-keywords-1 nil
  "Subdued level highlighting for Fortran mode.")

(defconst fortran-font-lock-keywords-2 nil
  "Medium level highlighting for Fortran mode.")

(defconst fortran-font-lock-keywords-3 nil
  "Gaudy level highlighting for Fortran mode.")

(let ((comment-chars "c!*")
      (fortran-type-types
;     (make-regexp
;      (let ((simple-types '("character" "byte" "integer" "logical"
;			    "none" "real" "complex"
;			    "double[ \t]*precision" "double[ \t]*complex"))
;	    (structured-types '("structure" "union" "map"))
;	    (other-types '("record" "dimension" "parameter" "common" "save"
;			   "external" "intrinsic" "data" "equivalence")))
;	(append
;	 (mapcar (lambda (x) (concat "implicit[ \t]*" x)) simple-types)
;	 simple-types
;	 (mapcar (lambda (x) (concat "end[ \t]*" x)) structured-types)
;	 structured-types
;	 other-types)))
	  (concat "byte\\|c\\(haracter\\|om\\(mon\\|plex\\)\\)\\|"
                  "d\\(ata\\|imension\\|ouble"
                  "[ \t]*\\(complex\\|precision\\)\\)\\|"
                  "e\\(nd[ \t]*\\(map\\|structure\\|union\\)\\|"
                  "quivalence\\|xternal\\)\\|"
                  "i\\(mplicit[ \t]*\\(byte\\|"
                  "c\\(haracter\\|omplex\\)\\|"
                  "double[ \t]*\\(complex\\|precision\\)\\|"
                  "integer\\|logical\\|none\\|real\\)\\|"
                  "nt\\(eger\\|rinsic\\)\\)\\|"
                  "logical\\|map\\|none\\|parameter\\|re\\(al\\|cord\\)\\|"
                  "s\\(ave\\|tructure\\)\\|union"))
	 (fortran-keywords
;	  ("continue" "format" "end" "enddo" "if" "then" "else" "endif"
;	   "elseif" "while" "inquire" "stop" "return" "include" "open"
;	   "close" "read" "write" "format" "print")
	  (concat "c\\(lose\\|ontinue\\)\\|"
		  "e\\(lse\\(\\|if\\)\\|nd\\(\\|do\\|if\\)\\)\\|format\\|"
		  "i\\(f\\|n\\(clude\\|quire\\)\\)\\|open\\|print\\|"
		  "re\\(ad\\|turn\\)\\|stop\\|then\\|w\\(hile\\|rite\\)"))
        (fortran-logicals
;       ("and" "or" "not" "lt" "le" "eq" "ge" "gt" "ne" "true" "false")
         "and\\|eq\\|false\\|g[et]\\|l[et]\\|n\\(e\\|ot\\)\\|or\\|true"))

  (setq fortran-font-lock-keywords-1
   (list
    ;;
    ;; Fontify syntactically (assuming strings cannot be quoted or span lines).
    (cons (concat "^[" comment-chars "].*") 'font-lock-comment-face)
    '(fortran-match-!-comment . font-lock-comment-face)
    (list (concat "^[^" comment-chars "\t\n]" (make-string 71 ?.) "\\(.*\\)")
	  '(1 font-lock-comment-face))
    '("'[^'\n]*'?" . font-lock-string-face)
    ;;
    ;; Program, subroutine and function declarations, plus calls.
    (list (concat "\\<\\(block[ \t]*data\\|call\\|entry\\|function\\|"
		  "program\\|subroutine\\)\\>[ \t]*\\(\\sw+\\)?")
	  '(1 font-lock-keyword-face)
	  '(2 font-lock-function-name-face nil t))))

  (setq fortran-font-lock-keywords-2
   (append fortran-font-lock-keywords-1
    (list
     ;;
     ;; Fontify all type specifiers (must be first; see below).
     (cons (concat "\\<\\(" fortran-type-types "\\)\\>") 'font-lock-type-face)
     ;;
     ;; Fontify all builtin keywords (except logical, do and goto; see below).
     (concat "\\<\\(" fortran-keywords "\\)\\>")
     ;;
     ;; Fontify all builtin operators.
     (concat "\\.\\(" fortran-logicals "\\)\\.")
     ;;
     ;; Fontify do/goto keywords and targets, and goto tags.
     (list "\\<\\(do\\|go *to\\)\\>[ \t]*\\([0-9]+\\)?"
	   '(1 font-lock-keyword-face)
	   '(2 font-lock-reference-face nil t))
     (cons "^ *\\([0-9]+\\)" 'font-lock-reference-face))))

  (setq fortran-font-lock-keywords-3
   (append
    ;;
    ;; The list `fortran-font-lock-keywords-1'.
    fortran-font-lock-keywords-1
    ;;
    ;; Fontify all type specifiers plus their declared items.
    (list
     (list (concat "\\<\\(" fortran-type-types "\\)\\>[ \t(/]*\\(*\\)?")
	   ;; Fontify the type specifier.
	   '(1 font-lock-type-face)
	   ;; Fontify each declaration item (or just the /.../ block name).
	   '(font-lock-match-c-style-declaration-item-and-skip-to-next
	     ;; Start after any *(...) expression.
	     (and (match-beginning 15) (forward-sexp 1))
	     ;; No need to clean up.
	     nil
	     ;; Fontify as a variable name, functions are fontified elsewhere.
	     (1 font-lock-variable-name-face nil t))))
    ;;
    ;; Things extra to `fortran-font-lock-keywords-3' (must be done first).
    (list
     ;;
     ;; Fontify goto-like `err=label'/`end=label' in read/write statements.
     '(", *\\(e\\(nd\\|rr\\)\\)\\> *\\(= *\\([0-9]+\\)\\)?"
       (1 font-lock-keyword-face) (4 font-lock-reference-face nil t))
     ;;
     ;; Highlight standard continuation character and in a TAB-formatted line.
     '("^     \\([^ 0]\\)" 1 font-lock-string-face)
     '("^\t\\([1-9]\\)" 1 font-lock-string-face))
    ;;
    ;; The list `fortran-font-lock-keywords-2' less that for types (see above).
    (cdr (nthcdr (length fortran-font-lock-keywords-1)
		 fortran-font-lock-keywords-2))))
  )

(defvar fortran-font-lock-keywords fortran-font-lock-keywords-1
  "Default expressions to highlight in Fortran mode.")

(defvar fortran-imenu-generic-expression
  ;; These patterns could be confused by sequence nos. in cols 72+ and
  ;; don't allow continuations everywhere.
  (list
   (list
    nil
    ;; Lines below are: 1. leading whitespace; 2. function
    ;; declaration with optional type, e.g. `real', `real*4',
    ;; character(*), `double precision' and possible statement
    ;; continuation; 3. untyped declarations; 4. the variable to
    ;; index.  [This will be fooled by `end function' allowed by G77.
    ;; Also, it assumes sensible whitespace is employed.]
    (concat "^\\s-+\\(\
\\(\\sw\\|\\s-\\|[*()+]\\)*\\<function\\|\
subroutine\\|entry\\|block\\s-*data\\|program\\)[ \t" fortran-continuation-string "]+\
\\(\\sw+\\)")
    3)
   ;; Un-named block data
   (list nil "^\\s-+\\(block\\s-*data\\)\\s-*$" 1))
  "imenu generic expression for `imenu-default-create-index-function'.")

(defvar fortran-mode-map ()
  "Keymap used in Fortran mode.")
(if fortran-mode-map
    ()
  (setq fortran-mode-map (make-sparse-keymap))
  (define-key fortran-mode-map ";" 'fortran-abbrev-start)
  (define-key fortran-mode-map "\C-c;" 'fortran-comment-region)
  (define-key fortran-mode-map "\e\C-a" 'beginning-of-fortran-subprogram)
  (define-key fortran-mode-map "\e\C-e" 'end-of-fortran-subprogram)
  (define-key fortran-mode-map "\e;" 'fortran-indent-comment)
  (define-key fortran-mode-map "\e\C-h" 'mark-fortran-subprogram)
  (define-key fortran-mode-map "\e\n" 'fortran-split-line)
  (define-key fortran-mode-map "\n" 'fortran-indent-new-line)
  (define-key fortran-mode-map "\e\C-q" 'fortran-indent-subprogram)
  (define-key fortran-mode-map "\C-c\C-w" 'fortran-window-create-momentarily)
  (define-key fortran-mode-map "\C-c\C-r" 'fortran-column-ruler)
  (define-key fortran-mode-map "\C-c\C-p" 'fortran-previous-statement)
  (define-key fortran-mode-map "\C-c\C-n" 'fortran-next-statement)
  (define-key fortran-mode-map "\C-c\C-d" 'fortran-join-line)
  (define-key fortran-mode-map "\t" 'fortran-indent-line)
  (define-key fortran-mode-map "0" 'fortran-electric-line-number)
  (define-key fortran-mode-map "1" 'fortran-electric-line-number)
  (define-key fortran-mode-map "2" 'fortran-electric-line-number)
  (define-key fortran-mode-map "3" 'fortran-electric-line-number)
  (define-key fortran-mode-map "4" 'fortran-electric-line-number)
  (define-key fortran-mode-map "5" 'fortran-electric-line-number)
  (define-key fortran-mode-map "6" 'fortran-electric-line-number)
  (define-key fortran-mode-map "7" 'fortran-electric-line-number)
  (define-key fortran-mode-map "8" 'fortran-electric-line-number)
  (define-key fortran-mode-map "9" 'fortran-electric-line-number)

  ;; Menu
  (unless (boundp 'fortran-mode-menu)
    (easy-menu-define
     fortran-mode-menu fortran-mode-map ""
     '("Fortran"
       ["Toggle Auto-fill" fortran-auto-fill-mode :style toggle
        :selected (eq auto-fill-function 'fortran-do-auto-fill)]
       ["Toggle abbrev-mode" abbrev-mode :style toggle :selected abbrev-mode]
       "----"
       ["Comment-out Region" fortran-comment-region mark-active]
       ["Uncomment-out region"
        (fortran-comment-region (region-beginning) (region-end) 1)
        mark-active]
       ["Indent Region" indent-region mark-active]
       ["Indent Subprogram" fortran-indent-subprogram t]
       "----"
       ["Beginning of Subprogram" beginning-of-fortran-subprogram t]
       ["End of Subprogram" end-of-fortran-subprogram t]
       ("Mark"
        ["Subprogram" mark-fortran-subprogram t]
        ["IF Block" fortran-mark-if t]
        ["DO Block" fortran-mark-do t])
       ["Narrow to Subprogram" fortran-narrow-to-subprogram t]
       ["Widen" widen t]
       "----"
       ["Temporary column ruler" fortran-column-ruler t]
       ["72-column window" fortran-window-create t]
       ["Full Width Window"
        (enlarge-window-horizontally (- (frame-width) (window-width)))
        (< (window-width) (frame-width))]
       ["Momentary 72-column window" fortran-window-create-momentarily t]
       "----"
       ["Break Line at Point" fortran-split-line t]
       ["Join Continuation Line" fortran-join-line t]
       "----"
       ["Add imenu menu"
        (progn (imenu-add-to-menubar "Index")
               ;; Prod menu bar to update -- is this the right way?
               (menu-bar-mode 1))
        t]))))

(defvar fortran-mode-abbrev-table nil)
(if fortran-mode-abbrev-table
    ()
  (let ((ac abbrevs-changed))
    (define-abbrev-table 'fortran-mode-abbrev-table ())
    (define-abbrev fortran-mode-abbrev-table  ";au"  "automatic" nil)
    (define-abbrev fortran-mode-abbrev-table  ";b"   "byte" nil)
    (define-abbrev fortran-mode-abbrev-table  ";bd"  "block data" nil)
    (define-abbrev fortran-mode-abbrev-table  ";ch"  "character" nil)
    (define-abbrev fortran-mode-abbrev-table  ";cl"  "close" nil)
    (define-abbrev fortran-mode-abbrev-table  ";c"   "continue" nil)
    (define-abbrev fortran-mode-abbrev-table  ";cm"  "common" nil)
    (define-abbrev fortran-mode-abbrev-table  ";cx"  "complex" nil)
    (define-abbrev fortran-mode-abbrev-table  ";df"  "define" nil)
    (define-abbrev fortran-mode-abbrev-table  ";di"  "dimension" nil)
    (define-abbrev fortran-mode-abbrev-table  ";do"  "double" nil)
    (define-abbrev fortran-mode-abbrev-table  ";dc"  "double complex" nil)
    (define-abbrev fortran-mode-abbrev-table  ";dp"  "double precision" nil)
    (define-abbrev fortran-mode-abbrev-table  ";dw"  "do while" nil)
    (define-abbrev fortran-mode-abbrev-table  ";e"   "else" nil)
    (define-abbrev fortran-mode-abbrev-table  ";ed"  "enddo" nil)
    (define-abbrev fortran-mode-abbrev-table  ";el"  "elseif" nil)
    (define-abbrev fortran-mode-abbrev-table  ";en"  "endif" nil)
    (define-abbrev fortran-mode-abbrev-table  ";eq"  "equivalence" nil)
    (define-abbrev fortran-mode-abbrev-table  ";ew"  "endwhere" nil)
    (define-abbrev fortran-mode-abbrev-table  ";ex"  "external" nil)
    (define-abbrev fortran-mode-abbrev-table  ";ey"  "entry" nil)
    (define-abbrev fortran-mode-abbrev-table  ";f"   "format" nil)
    (define-abbrev fortran-mode-abbrev-table  ";fa"  ".false." nil)
    (define-abbrev fortran-mode-abbrev-table  ";fu"  "function" nil)
    (define-abbrev fortran-mode-abbrev-table  ";g"   "goto" nil)
    (define-abbrev fortran-mode-abbrev-table  ";im"  "implicit" nil)
    (define-abbrev fortran-mode-abbrev-table  ";ib"  "implicit byte" nil)
    (define-abbrev fortran-mode-abbrev-table  ";ic"  "implicit complex" nil)
    (define-abbrev fortran-mode-abbrev-table  ";ich" "implicit character" nil)
    (define-abbrev fortran-mode-abbrev-table  ";ii"  "implicit integer" nil)
    (define-abbrev fortran-mode-abbrev-table  ";il"  "implicit logical" nil)
    (define-abbrev fortran-mode-abbrev-table  ";ir"  "implicit real" nil)
    (define-abbrev fortran-mode-abbrev-table  ";inc" "include" nil)
    (define-abbrev fortran-mode-abbrev-table  ";in"  "integer" nil)
    (define-abbrev fortran-mode-abbrev-table  ";intr" "intrinsic" nil)
    (define-abbrev fortran-mode-abbrev-table  ";l"   "logical" nil)
    (define-abbrev fortran-mode-abbrev-table  ";n"   "namelist" nil)
    (define-abbrev fortran-mode-abbrev-table  ";o"   "open" nil) ; was ;op
    (define-abbrev fortran-mode-abbrev-table  ";pa"  "parameter" nil)
    (define-abbrev fortran-mode-abbrev-table  ";pr"  "program" nil)
    (define-abbrev fortran-mode-abbrev-table  ";ps"  "pause" nil)
    (define-abbrev fortran-mode-abbrev-table  ";p"   "print" nil)
    (define-abbrev fortran-mode-abbrev-table  ";rc"  "record" nil)
    (define-abbrev fortran-mode-abbrev-table  ";re"  "real" nil)
    (define-abbrev fortran-mode-abbrev-table  ";r"   "read" nil)
    (define-abbrev fortran-mode-abbrev-table  ";rt"  "return" nil)
    (define-abbrev fortran-mode-abbrev-table  ";rw"  "rewind" nil)
    (define-abbrev fortran-mode-abbrev-table  ";s"   "stop" nil)
    (define-abbrev fortran-mode-abbrev-table  ";sa"  "save" nil)
    (define-abbrev fortran-mode-abbrev-table  ";st"  "structure" nil)
    (define-abbrev fortran-mode-abbrev-table  ";sc"  "static" nil)
    (define-abbrev fortran-mode-abbrev-table  ";su"  "subroutine" nil)
    (define-abbrev fortran-mode-abbrev-table  ";tr"  ".true." nil)
    (define-abbrev fortran-mode-abbrev-table  ";ty"  "type" nil)
    (define-abbrev fortran-mode-abbrev-table  ";vo"  "volatile" nil)
    (define-abbrev fortran-mode-abbrev-table  ";w"   "write" nil)
    (define-abbrev fortran-mode-abbrev-table  ";wh"  "where" nil)
    (setq abbrevs-changed ac)))

(eval-when-compile (defvar imenu-syntax-alist nil)) ; silence compiler

;;;###autoload
(defun fortran-mode ()
  "Major mode for editing Fortran code.
\\[fortran-indent-line] indents the current Fortran line correctly.
DO statements must not share a common CONTINUE.

Type ;? or ;\\[help-command] to display a list of built-in\
 abbrevs for Fortran keywords.

Key definitions:
\\{fortran-mode-map}

Variables controlling indentation style and extra features:

 comment-start
    Normally nil in Fortran mode.  If you want to use comments
    starting with `!', set this to the string \"!\".
 fortran-do-indent
    Extra indentation within do blocks.  (default 3)
 fortran-if-indent
    Extra indentation within if blocks.  (default 3)
 fortran-structure-indent
    Extra indentation within structure, union, map and interface blocks.
    (default 3)
 fortran-continuation-indent
    Extra indentation applied to continuation statements.  (default 5)
 fortran-comment-line-extra-indent
    Amount of extra indentation for text within full-line comments. (default 0)
 fortran-comment-indent-style
    nil    means don't change indentation of text in full-line comments,
    fixed  means indent that text at `fortran-comment-line-extra-indent' beyond
           the value of `fortran-minimum-statement-indent-fixed' (for fixed
           format continuation style) or `fortran-minimum-statement-indent-tab'
           (for TAB format continuation style).
    relative  means indent at `fortran-comment-line-extra-indent' beyond the
 	      indentation for a line of code.
    (default 'fixed)
 fortran-comment-indent-char
    Single-character string to be inserted instead of space for
    full-line comment indentation.  (default \" \")
 fortran-minimum-statement-indent-fixed
    Minimum indentation for Fortran statements in fixed format mode. (def.6)
 fortran-minimum-statement-indent-tab
    Minimum indentation for Fortran statements in TAB format mode. (default 9)
 fortran-line-number-indent
    Maximum indentation for line numbers.  A line number will get
    less than this much indentation if necessary to avoid reaching
    column 5.  (default 1)
 fortran-check-all-num-for-matching-do
    Non-nil causes all numbered lines to be treated as possible \"continue\"
    statements.  (default nil)
 fortran-blink-matching-if
    Non-nil causes \\[fortran-indent-line] on an ENDIF statement to blink on
    matching IF.  Also, from an ENDDO statement, blink on matching DO [WHILE]
    statement.  (default nil)
 fortran-continuation-string
    Single-character string to be inserted in column 5 of a continuation
    line.  (default \"$\")
 fortran-comment-region
    String inserted by \\[fortran-comment-region] at start of each line in
    region.  (default \"c$$$\")
 fortran-electric-line-number
    Non-nil causes line number digits to be moved to the correct column
    as typed.  (default t)
 fortran-break-before-delimiters
    Non-nil causes `fortran-fill' breaks lines before delimiters.
    (default t)

Turning on Fortran mode calls the value of the variable `fortran-mode-hook'
with no args, if that value is non-nil."
  (interactive)
  (kill-all-local-variables)
  (setq local-abbrev-table fortran-mode-abbrev-table)
  (set-syntax-table fortran-mode-syntax-table)
  ;; Font Lock mode support.
  (make-local-variable 'font-lock-defaults)
  (setq font-lock-defaults '((fortran-font-lock-keywords
			      fortran-font-lock-keywords-1
			      fortran-font-lock-keywords-2
			      fortran-font-lock-keywords-3)
			     t t ((?/ . "$/") ("_$" . "w"))))
  (make-local-variable 'fortran-break-before-delimiters)
  (setq fortran-break-before-delimiters t)
  (make-local-variable 'indent-line-function)
  (setq indent-line-function 'fortran-indent-line)
  (make-local-variable 'comment-indent-function)
  (setq comment-indent-function 'fortran-comment-hook)
  (make-local-variable 'comment-line-start-skip)
  (setq comment-line-start-skip
	"^[Cc*]\\(\\([^ \t\n]\\)\\2\\2*\\)?[ \t]*\\|^#.*")
  (make-local-variable 'comment-line-start)
  (setq comment-line-start "c")
  (make-local-variable 'comment-start-skip)
  (setq comment-start-skip "![ \t]*")
  (make-local-variable 'comment-start)
  (setq comment-start nil)
  (make-local-variable 'require-final-newline)
  (setq require-final-newline t)
  (make-local-variable 'abbrev-all-caps)
  (setq abbrev-all-caps t)
  (make-local-variable 'indent-tabs-mode)
  (setq indent-tabs-mode nil)
;;;(setq abbrev-mode t) ; ?? (abbrev-mode 1) instead??
  (setq fill-column 72) ; Already local?
  (use-local-map fortran-mode-map)
  (setq mode-name "Fortran")
  (setq major-mode 'fortran-mode)
;;;(make-local-variable 'fortran-tab-mode)
  (make-local-variable 'fortran-comment-line-extra-indent)
  (make-local-variable 'fortran-minimum-statement-indent-fixed)
  (make-local-variable 'fortran-minimum-statement-indent-tab)
  (make-local-variable 'fortran-column-ruler-fixed)
  (make-local-variable 'fortran-column-ruler-tab)
  (make-local-variable 'fortran-tab-mode-string)
  (setq fortran-tab-mode-string " TAB-format")
  (setq indent-tabs-mode (fortran-analyze-file-format))
  (setq imenu-case-fold-search t)
  (make-local-variable 'imenu-generic-expression)
  (setq imenu-generic-expression fortran-imenu-generic-expression)
  (setq imenu-syntax-alist '(("_$" . "w")))
  (run-hooks 'fortran-mode-hook))

(defun fortran-comment-hook ()
  (save-excursion
    (skip-chars-backward " \t")
    (max (+ 1 (current-column))
	 comment-column)))

(defun fortran-indent-comment ()
  "Align or create comment on current line.
Existing comments of all types are recognized and aligned.
If the line has no comment, a side-by-side comment is inserted and aligned
if the value of  `comment-start'  is not nil.
Otherwise, a separate-line comment is inserted, on this line
or on a new line inserted before this line if this line is not blank."
  (interactive)
  (beginning-of-line)
  ;; Recognize existing comments of either kind.
  (cond ((looking-at comment-line-start-skip)
	 (fortran-indent-line))
	((fortran-find-comment-start-skip) ; catches any inline comment and
					; leaves point after comment-start-skip
	 (if comment-start-skip
	     (progn (goto-char (match-beginning 0))
		    (if (not (= (current-column) (fortran-comment-hook)))
			(progn (delete-horizontal-space)
			       (indent-to (fortran-comment-hook)))))
	   (end-of-line)))        ; otherwise goto end of line or sth else?
	;; No existing comment.
	;; If side-by-side comments are defined, insert one,
	;; unless line is now blank.
	((and comment-start (not (looking-at "^[ \t]*$")))
	 (end-of-line)
	 (delete-horizontal-space)
	 (indent-to (fortran-comment-hook))
	 (insert comment-start))
	;; Else insert separate-line comment, making a new line if nec.
	(t
	 (if (looking-at "^[ \t]*$")
	     (delete-horizontal-space)
	   (beginning-of-line)
	   (insert "\n")
	   (forward-char -1))
	 (insert comment-line-start)
	 (insert-char (if (stringp fortran-comment-indent-char)
			  (aref fortran-comment-indent-char 0)
			fortran-comment-indent-char)
		      (- (calculate-fortran-indent) (current-column))))))

(defun fortran-comment-region (beg-region end-region arg)
  "Comments every line in the region.
Puts `fortran-comment-region' at the beginning of every line in the region.
BEG-REGION and END-REGION are args which specify the region boundaries.
With non-nil ARG, uncomments the region."
  (interactive "*r\nP")
  (let ((end-region-mark (make-marker)) (save-point (point-marker)))
    (set-marker end-region-mark end-region)
    (goto-char beg-region)
    (beginning-of-line)
    (if (not arg)			;comment the region
	(progn (insert fortran-comment-region)
	       (while (and  (= (forward-line 1) 0)
			    (< (point) end-region-mark))
		 (insert fortran-comment-region)))
      (let ((com (regexp-quote fortran-comment-region))) ;uncomment the region
	(if (looking-at com)
	    (delete-region (point) (match-end 0)))
	(while (and  (= (forward-line 1) 0)
		     (< (point) end-region-mark))
	  (if (looking-at com)
	      (delete-region (point) (match-end 0))))))
    (goto-char save-point)
    (set-marker end-region-mark nil)
    (set-marker save-point nil)))

(defun fortran-abbrev-start ()
  "Typing ;\\[help-command] or ;? lists all the Fortran abbrevs.
Any other key combination is executed normally."
  (interactive)
  (let (c)
    (insert last-command-char)
    (if (or (eq (setq c (read-event)) ??)    ;insert char if not equal to `?'
	    (eq c help-char))
	(fortran-abbrev-help)
      (setq unread-command-events (list c)))))

(defun fortran-abbrev-help ()
  "List the currently defined abbrevs in Fortran mode."
  (interactive)
  (message "Listing abbrev table...")
  (display-buffer (fortran-prepare-abbrev-list-buffer))
  (message "Listing abbrev table...done"))

(defun fortran-prepare-abbrev-list-buffer ()
  (save-excursion
    (set-buffer (get-buffer-create "*Abbrevs*"))
    (erase-buffer)
    (insert-abbrev-table-description 'fortran-mode-abbrev-table t)
    (goto-char (point-min))
    (set-buffer-modified-p nil)
    (edit-abbrevs-mode))
  (get-buffer-create "*Abbrevs*"))

(defun fortran-column-ruler ()
  "Insert a column ruler momentarily above current line, till next keystroke.
The ruler is defined by the value of `fortran-column-ruler-fixed' when in fixed
format mode, and `fortran-column-ruler-tab' when in TAB format mode.
The key typed is executed unless it is SPC."
  (interactive)
  (momentary-string-display
   (if indent-tabs-mode
       fortran-column-ruler-tab
     fortran-column-ruler-fixed)
   (save-excursion
     (beginning-of-line)
     (if (eq (window-start (selected-window))
	     (window-point (selected-window)))
	 (progn (forward-line) (point))
       (point)))
   nil "Type SPC or any command to erase ruler."))

(defun fortran-window-create ()
  "Make the window 72 columns wide.
See also `fortran-window-create-momentarily'."
  (interactive)
  (condition-case error
      (progn
	(let ((window-min-width 2))
	  (if (< (window-width) (frame-width))
	      (enlarge-window-horizontally (- (frame-width)
					      (window-width) 1)))
	  (split-window-horizontally 73)
	  (other-window 1)
	  (switch-to-buffer " fortran-window-extra" t)
	  (select-window (previous-window))))
    (error (message "No room for Fortran window.")
	   'error)))

(defun fortran-window-create-momentarily (&optional arg)
  "Momentarily make the window 72 columns wide.
Optional ARG non-nil and non-unity disables the momentary feature.
See also `fortran-window-create'."
  (interactive "p")
  (if (or (not arg)
	  (= arg 1))
      (save-window-excursion
	(if (not (equal (fortran-window-create) 'error))
	    (progn (message "Type SPC to continue editing.")
		   (let ((char (read-event)))
		     (or (equal char (string-to-char " "))
			 (setq unread-command-events (list char)))))))
    (fortran-window-create)))

(defun fortran-split-line ()
  "Break line at point and insert continuation marker and alignment."
  (interactive)
  (delete-horizontal-space)
  (if (save-excursion (beginning-of-line) (looking-at comment-line-start-skip))
      (insert "\n" comment-line-start " ")
    (if indent-tabs-mode
	(progn
	  (insert "\n\t")
	  (insert-char (fortran-numerical-continuation-char) 1))
      (insert "\n " fortran-continuation-string)));Space after \n important
  (fortran-indent-line))		;when the cont string is C, c or *.

(defun fortran-join-line ()
  "Join a continuation line to the previous one and re-indent."
  (interactive)
  (save-excursion
    (beginning-of-line)
    (cond ((looking-at "     \\S-")
           (delete-region (1- (point)) (+ (point) 7)))
          ((looking-at "&")
           (delete-region (1- (point)) (1+ (point))))
          ((looking-at " *\t[1-9]")
           (apply 'delete-region (match-data))
           (delete-backward-char 1))
          (t (error "This isn't a continuation line")))
    (just-one-space)
    (fortran-indent-line)))

(defun fortran-numerical-continuation-char ()
  "Return a digit for tab-digit style of continuation lines.
If, previous line is a tab-digit continuation line, returns that digit
plus one.  Otherwise return 1.  Zero not allowed."
  (save-excursion
    (forward-line -1)
    (if (looking-at "\t[1-9]")
	(+ ?1 (% (- (char-after (+ (point) 1)) ?0) 9))
      ?1)))

(defun delete-horizontal-regexp (chars)
  "Delete all characters in CHARS around point.
CHARS is like the inside of a [...] in a regular expression
except that ] is never special and \ quotes ^, - or \."
  (interactive "*s")
  (skip-chars-backward chars)
  (delete-region (point) (progn (skip-chars-forward chars) (point))))

(defun fortran-electric-line-number (arg)
  "Self insert, but if part of a Fortran line number indent it automatically.
Auto-indent does not happen if a numeric ARG is used."
  (interactive "P")
  (if (or arg (not fortran-electric-line-number))
      (if arg
	  (self-insert-command (prefix-numeric-value arg))
	(self-insert-command 1))
    (if (or (and (= 5 (current-column))
		 (save-excursion
		   (beginning-of-line)
		   (looking-at "     ")));In col 5 with only spaces to left.
	    (and (= (if indent-tabs-mode
		  fortran-minimum-statement-indent-tab
		fortran-minimum-statement-indent-fixed) (current-column))
		 (save-excursion
		   (beginning-of-line)
		   (looking-at "\t"));In col 8 with a single tab to the left.
		 (not (or (eq last-command 'fortran-indent-line)
			  (eq last-command
			      'fortran-indent-new-line))))
	    (save-excursion
	      (re-search-backward "[^ \t0-9]"
				  (save-excursion
				    (beginning-of-line)
				    (point))
				  t)) ;not a line number
	    (looking-at "[0-9]")	;within a line number
	    )
	(self-insert-command (prefix-numeric-value arg))
      (skip-chars-backward " \t")
      (insert last-command-char)
      (fortran-indent-line))))

(defun beginning-of-fortran-subprogram ()
  "Moves point to the beginning of the current Fortran subprogram."
  (interactive)
  (let ((case-fold-search t))
    (beginning-of-line -1)
    (re-search-backward "^[ \t0-9]*end\\b[ \t]*[^ \t=(a-z]" nil 'move)
    (if (looking-at "^[ \t0-9]*end\\b[ \t]*[^ \t=(a-z]")
	(forward-line 1))))

(defun end-of-fortran-subprogram ()
  "Moves point to the end of the current Fortran subprogram."
  (interactive)
  (let ((case-fold-search t))
    (beginning-of-line 2)
    (re-search-forward "^[ \t0-9]*end\\b[ \t]*[^ \t=(a-z]" nil 'move)
    (goto-char (match-beginning 0))
    (forward-line 1)))

(defun mark-fortran-subprogram ()
  "Put mark at end of Fortran subprogram, point at beginning.
The marks are pushed."
  (interactive)
  (end-of-fortran-subprogram)
  (push-mark (point))
  (beginning-of-fortran-subprogram))

(defun fortran-previous-statement ()
  "Moves point to beginning of the previous Fortran statement.
Returns `first-statement' if that statement is the first
non-comment Fortran statement in the file, and nil otherwise."
  (interactive)
  (let (not-first-statement continue-test)
    (beginning-of-line)
    (setq continue-test
	  (and
	   (not (looking-at comment-line-start-skip))
	   (or (looking-at
	        (concat "[ \t]*" (regexp-quote fortran-continuation-string)))
	       (or (looking-at "     [^ 0\n]")
		   (looking-at "\t[1-9]")))))
    (while (and (setq not-first-statement (= (forward-line -1) 0))
		(or (looking-at comment-line-start-skip)
		    (looking-at "[ \t]*$")
		    (looking-at "     [^ 0\n]")
		    (looking-at "\t[1-9]")
		    (looking-at (concat "[ \t]*"  comment-start-skip)))))
    (cond ((and continue-test
		(not not-first-statement))
	   (message "Incomplete continuation statement."))
	  (continue-test
	   (fortran-previous-statement))
	  ((not not-first-statement)
	   'first-statement))))

(defun fortran-next-statement ()
  "Moves point to beginning of the next Fortran statement.
Returns `last-statement' if that statement is the last
non-comment Fortran statement in the file, and nil otherwise."
  (interactive)
  (let (not-last-statement)
    (beginning-of-line)
    (while (and (setq not-last-statement
		      (and (= (forward-line 1) 0)
			   (not (eobp))))
 		(or (looking-at comment-line-start-skip)
 		    (looking-at "[ \t]*$")
 		    (looking-at "     [^ 0\n]")
 		    (looking-at "\t[1-9]")
 		    (looking-at (concat "[ \t]*"  comment-start-skip)))))
    (if (not not-last-statement)
 	'last-statement)))

(defun fortran-narrow-to-subprogram ()
  "Make text outside the current subprogram invisible.
The subprogram visible is the one that contains or follows point."
  (interactive)
        (save-excursion
          (mark-fortran-subprogram)
          (narrow-to-region (region-beginning)
                            (region-end))))

(defun fortran-blink-matching-if ()
  ;; From a Fortran ENDIF statement, blink the matching IF statement.
  (let ((top-of-window (window-start)) matching-if
	(endif-point (point)) message)
    (if (save-excursion (beginning-of-line)
			(skip-chars-forward " \t0-9")
			(looking-at "end[ \t]*if\\b"))
	(progn
          (if (not (setq matching-if (fortran-beginning-if)))
              (setq message "No matching if.")
            (if (< matching-if top-of-window)
                (save-excursion
                  (goto-char matching-if)
                  (beginning-of-line)
                  (setq message
                        (concat "Matches "
                                (buffer-substring
                                 (point) (progn (end-of-line) (point))))))))
	  (if message
	      (message "%s" message)
	    (goto-char matching-if)
	    (sit-for 1)
	    (goto-char endif-point))))))

(defun fortran-blink-matching-do ()
  ;; From a Fortran ENDDO statement, blink on the matching DO or DO WHILE
  ;; statement.  This is basically copied from fortran-blink-matching-if.
  (let ((top-of-window (window-start)) matching-do
	(enddo-point (point)) message)
    (if (save-excursion (beginning-of-line)
			(skip-chars-forward " \t0-9")
			(looking-at "end[ \t]*do\\b"))
	(progn
          (if (not (setq matching-do (fortran-beginning-do)))
              (setq message "No matching do.")
            (if (< matching-do top-of-window)
                (save-excursion
                  (goto-char matching-do)
                  (beginning-of-line)
                  (setq message
                        (concat "Matches "
                                (buffer-substring
                                 (point) (progn (end-of-line) (point))))))))
	  (if message
	      (message "%s" message)
	    (goto-char matching-do)
	    (sit-for 1)
	    (goto-char enddo-point))))))

(defun fortran-mark-do ()
  "Put mark at end of Fortran DO [WHILE]-ENDDO construct, point at beginning.
The marks are pushed."
  (interactive)
  (let (enddo-point do-point)
    (if (setq enddo-point (fortran-end-do))
        (if (not (setq do-point (fortran-beginning-do)))
            (message "No matching do.")
          ;; Set mark, move point.
          (goto-char enddo-point)
          (push-mark)
          (goto-char do-point)))))

(defun fortran-end-do ()
  ;; Search forward for first unmatched ENDDO.  Return point or nil.
  (if (save-excursion (beginning-of-line)
                      (skip-chars-forward " \t0-9")
                      (looking-at "end[ \t]*do\\b"))
      ;; Sitting on one.
      (match-beginning 0)
    ;; Search for one.
    (save-excursion
      (let ((count 1))
        (while (and (not (= count 0))
                    (not (eq (fortran-next-statement) 'last-statement))
                    ;; Keep local to subprogram
                    (not (looking-at "^[ \t0-9]*end\\b[ \t]*[^ \t=(a-z]")))

          (skip-chars-forward " \t0-9")
          (cond ((looking-at "end[ \t]*do\\b")
                 (setq count (- count 1)))
                ((looking-at "do[ \t]+[^0-9]")
                 (setq count (+ count 1)))))
        (and (= count 0)
             ;; All pairs accounted for.
             (point))))))

(defun fortran-beginning-do ()
  ;; Search backwards for first unmatched DO [WHILE].  Return point or nil.
  (if (save-excursion (beginning-of-line)
                      (skip-chars-forward " \t0-9")
                      (looking-at "do[ \t]+"))
      ;; Sitting on one.
      (match-beginning 0)
    ;; Search for one.
    (save-excursion
      (let ((count 1))
        (while (and (not (= count 0))
                    (not (eq (fortran-previous-statement) 'first-statement))
                    ;; Keep local to subprogram
                    (not (looking-at "^[ \t0-9]*end\\b[ \t]*[^ \t=(a-z]")))

          (skip-chars-forward " \t0-9")
          (cond ((looking-at "do[ \t]+[^0-9]")
                 (setq count (- count 1)))
                ((looking-at "end[ \t]*do\\b")
                 (setq count (+ count 1)))))

        (and (= count 0)
             ;; All pairs accounted for.
             (point))))))

(defun fortran-mark-if ()
  "Put mark at end of Fortran IF-ENDIF construct, point at beginning.
The marks are pushed."
  (interactive)
  (let (endif-point if-point)
    (if (setq endif-point (fortran-end-if))
        (if (not (setq if-point (fortran-beginning-if)))
            (message "No matching if.")
          ;; Set mark, move point.
          (goto-char endif-point)
          (push-mark)
          (goto-char if-point)))))

(defun fortran-end-if ()
  ;; Search forwards for first unmatched ENDIF.  Return point or nil.
  (if (save-excursion (beginning-of-line)
                      (skip-chars-forward " \t0-9")
                      (looking-at "end[ \t]*if\\b"))
      ;; Sitting on one.
      (match-beginning 0)
    ;; Search for one.  The point has been already been moved to first
    ;; letter on line but this should not cause troubles.
    (save-excursion
      (let ((count 1))
        (while (and (not (= count 0))
                    (not (eq (fortran-next-statement) 'last-statement))
                    ;; Keep local to subprogram.
                    (not (looking-at
                          "^[ \t0-9]*end\\b[ \t]*[^ \t=(a-z]")))

          (skip-chars-forward " \t0-9")
          (cond ((looking-at "end[ \t]*if\\b")
                 (setq count (- count 1)))

                ((looking-at "if[ \t]*(")
                 (save-excursion
                   (if (or
                        (looking-at ".*)[ \t]*then\\b[ \t]*[^ \t(=a-z0-9]")
                        (let (then-test) ; Multi-line if-then.
                          (while
                              (and (= (forward-line 1) 0)
                                   ;; Search forward for then.
                                   (or (looking-at "     [^ 0\n]")
                                       (looking-at "\t[1-9]"))
                                   (not
                                    (setq then-test
                                          (looking-at
                                           ".*then\\b[ \t]*[^ \t(=a-z0-9]")))))
                          then-test))
                       (setq count (+ count 1)))))))

        (and (= count 0)
             ;; All pairs accounted for.
             (point))))))

(defun fortran-beginning-if ()
  ;; Search backwards for first unmatched IF-THEN.  Return point or nil.
  (if (save-excursion
        ;; May be sitting on multi-line if-then statement, first move to
        ;; beginning of current statement.  Note: `fortran-previous-statement'
        ;; moves to previous statement *unless* current statement is first
        ;; one.  Only move forward if not first-statement.
        (if (not (eq (fortran-previous-statement) 'first-statement))
            (fortran-next-statement))
        (skip-chars-forward " \t0-9")
        (and
         (looking-at "if[ \t]*(")
         (save-match-data
           (or (looking-at ".*)[ \t]*then\\b[ \t]*[^ \t(=a-z0-9]")
               ;; Multi-line if-then.
               (let (then-test)
                 (while
                     (and (= (forward-line 1) 0)
                          ;; Search forward for then.
                          (or (looking-at "     [^ 0\n]")
                              (looking-at "\t[1-9]"))
                          (not
                           (setq then-test
                                 (looking-at
                                  ".*then\\b[ \t]*[^ \t(=a-z0-9]")))))
                 then-test)))))
      ;; Sitting on one.
      (match-beginning 0)
    ;; Search for one.
    (save-excursion
      (let ((count 1))
        (while (and (not (= count 0))
                    (not (eq (fortran-previous-statement) 'first-statement))
                    ;; Keep local to subprogram.
                    (not (looking-at
                          "^[ \t0-9]*end\\b[ \t]*[^ \t=(a-z]")))

          (skip-chars-forward " \t0-9")
          (cond ((looking-at "if[ \t]*(")
                 (save-excursion
                   (if (or
                        (looking-at ".*)[ \t]*then\\b[ \t]*[^ \t(=a-z0-9]")
                        (let (then-test) ; Multi-line if-then.
                          (while
                              (and (= (forward-line 1) 0)
                                   ;; Search forward for then.
                                   (or (looking-at "     [^ 0\n]")
                                       (looking-at "\t[1-9]"))
                                   (not
                                    (setq then-test
                                          (looking-at
                                           ".*then\\b[ \t]*[^ \t(=a-z0-9]")))))
                          then-test))
                       (setq count (- count 1)))))
                ((looking-at "end[ \t]*if\\b")
                 (setq count (+ count 1)))))

        (and (= count 0)
             ;; All pairs accounted for.
             (point))))))

(defun fortran-indent-line ()
  "Indent current Fortran line based on its contents and on previous lines."
  (interactive)
  (let ((cfi (calculate-fortran-indent)))
    (save-excursion
      (beginning-of-line)
      (if (or (not (= cfi (fortran-current-line-indentation)))
	      (and (re-search-forward "^[ \t]*[0-9]+" (+ (point) 4) t)
		   (not (fortran-line-number-indented-correctly-p))))
	  (fortran-indent-to-column cfi)
	(beginning-of-line)
	(if (and (not (looking-at comment-line-start-skip))
		 (fortran-find-comment-start-skip))
	    (fortran-indent-comment))))
    ;; Never leave point in left margin.
    (if (< (current-column) cfi)
	(move-to-column cfi))
    (if (and auto-fill-function
	     (> (save-excursion (end-of-line) (current-column)) fill-column))
	(save-excursion
	  (end-of-line)
	  (fortran-fill)))
    (if fortran-blink-matching-if
        (progn
	  (fortran-blink-matching-if)
	  (fortran-blink-matching-do)))))

(defun fortran-indent-new-line ()
  "Reindent the current Fortran line, insert a newline and indent the newline.
An abbrev before point is expanded if `abbrev-mode' is non-nil."
  (interactive)
  (if abbrev-mode (expand-abbrev))
  (save-excursion
    (beginning-of-line)
    (skip-chars-forward " \t")
    (if (or (looking-at "[0-9]")	;Reindent only where it is most
	    (looking-at "end")		;likely to be necessary
	    (looking-at "else")
	    (looking-at (regexp-quote fortran-continuation-string)))
	(fortran-indent-line)))
  (newline)
  (fortran-indent-line))

(defun fortran-indent-subprogram ()
  "Properly indent the Fortran subprogram which contains point."
  (interactive)
  (save-excursion
    (mark-fortran-subprogram)
    (message "Indenting subprogram...")
    (indent-region (point) (mark) nil))
  (message "Indenting subprogram...done."))

(defun calculate-fortran-indent ()
  "Calculates the Fortran indent column based on previous lines."
  (let (icol first-statement (case-fold-search t)
	     (fortran-minimum-statement-indent
	      (if indent-tabs-mode
		  fortran-minimum-statement-indent-tab
		fortran-minimum-statement-indent-fixed)))
    (save-excursion
      (setq first-statement (fortran-previous-statement))
      (if first-statement
	  (setq icol fortran-minimum-statement-indent)
	(progn
	  (if (= (point) (point-min))
	      (setq icol fortran-minimum-statement-indent)
	    (setq icol (fortran-current-line-indentation)))
	  (skip-chars-forward " \t0-9")
	  (cond ((looking-at "if[ \t]*(")
		 (if (or (looking-at ".*)[ \t]*then\\b[ \t]*[^ \t_$(=a-z0-9]")
			 (let (then-test)	;multi-line if-then
			   (while (and (= (forward-line 1) 0)
				       ;;search forward for then
				       (or (looking-at "     [^ 0\n]")
					   (looking-at "\t[1-9]"))
				       (not (setq then-test (looking-at
							     ".*then\\b[ \t]\
*[^ \t_$(=a-z0-9]")))))
			   then-test))
		     (setq icol (+ icol fortran-if-indent))))
		((looking-at "\\(else\\|elseif\\)\\b")
		 (setq icol (+ icol fortran-if-indent)))
		((looking-at "select[ \t]*case[ \t](.*)\\b")
		 (setq icol (+ icol fortran-if-indent)))
		((looking-at "case[ \t]*(.*)[ \t]*\n")
		 (setq icol (+ icol fortran-if-indent)))
		((looking-at "case[ \t]*default\\b")
		 (setq icol (+ icol fortran-if-indent)))
		((looking-at "\\(otherwise\\|else[ \t]*where\\)\\b")
		 (setq icol (+ icol fortran-if-indent)))
		((looking-at "where[ \t]*(.*)[ \t]*\n")
		 (setq icol (+ icol fortran-if-indent)))
		((looking-at "do\\b")
		 (setq icol (+ icol fortran-do-indent)))
		((looking-at
		  "\\(structure\\|union\\|map\\|interface\\)\\b[ \t]*[^ \t=(a-z]")
		 (setq icol (+ icol fortran-structure-indent)))
		((looking-at "end\\b[ \t]*[^ \t=(a-z]")
		 ;; Previous END resets indent to minimum
		 (setq icol fortran-minimum-statement-indent))))))
    (save-excursion
      (beginning-of-line)
      (cond ((looking-at "[ \t]*$"))
	    ((looking-at comment-line-start-skip)
	     (cond ((eq fortran-comment-indent-style 'relative)
		    (setq icol (+ icol fortran-comment-line-extra-indent)))
		   ((eq fortran-comment-indent-style 'fixed)
		    (setq icol (+ fortran-minimum-statement-indent
				  fortran-comment-line-extra-indent))))
	     (setq fortran-minimum-statement-indent 0))
	    ((or (looking-at (concat "[ \t]*"
				     (regexp-quote
				      fortran-continuation-string)))
		 (looking-at "     [^ 0\n]")
		 (looking-at "\t[1-9]"))
	     (setq icol (+ icol fortran-continuation-indent)))
	    ((looking-at "[ \t]*#")	; Check for cpp directive.
	     (setq fortran-minimum-statement-indent 0 icol 0))
	    (first-statement)
	    ((and fortran-check-all-num-for-matching-do
		  (looking-at "[ \t]*[0-9]+")
		  (fortran-check-for-matching-do))
	     (setq icol (- icol fortran-do-indent)))
	    (t
	     (skip-chars-forward " \t0-9")
	     (cond ((looking-at "end[ \t]*if\\b")
		    (setq icol (- icol fortran-if-indent)))
		   ((looking-at "\\(else\\|elseif\\)\\b")
		    (setq icol (- icol fortran-if-indent)))
                   ((looking-at "case[ \t]*(.*)[ \t]*\n")
		    (setq icol (- icol fortran-if-indent)))
                   ((looking-at "case[ \t]*default\\b")
		    (setq icol (- icol fortran-if-indent)))
		   ((looking-at "\\(otherwise\\|else[ \t]*where\\)\\b")
		    (setq icol (- icol fortran-if-indent)))
		   ((looking-at "end[ \t]*where\\b")
		    (setq icol (- icol fortran-if-indent)))
		   ((and (looking-at "continue\\b")
			 (fortran-check-for-matching-do))
		    (setq icol (- icol fortran-do-indent)))
		   ((looking-at "end[ \t]*do\\b")
		    (setq icol (- icol fortran-do-indent)))
		   ((looking-at
		     "end[ \t]*\
\\(structure\\|union\\|map\\|interface\\)\\b[ \t]*[^ \t=(a-z]")
		    (setq icol (- icol fortran-structure-indent)))
		   ((looking-at
		     "end[ \t]*select\\b[ \t]*[^ \t=(a-z]")
		    (setq icol (- icol fortran-if-indent)))
		   ((and (looking-at "end\\b[ \t]*[^ \t=(a-z]")
			 (not (= icol fortran-minimum-statement-indent)))
 		    (message "Warning: `end' not in column %d.  Probably\
 an unclosed block." fortran-minimum-statement-indent))))))
    (max fortran-minimum-statement-indent icol)))

(defun fortran-current-line-indentation ()
  "Indentation of current line, ignoring Fortran line number or continuation.
This is the column position of the first non-whitespace character
aside from the line number and/or column 5/8 line-continuation character.
For comment lines, returns indentation of the first
non-indentation text within the comment."
  (save-excursion
    (beginning-of-line)
    (cond ((looking-at comment-line-start-skip)
	   (goto-char (match-end 0))
	   (skip-chars-forward
	    (if (stringp fortran-comment-indent-char)
		fortran-comment-indent-char
	      (char-to-string fortran-comment-indent-char))))
	  ((or (looking-at "     [^ 0\n]")
	       (looking-at "\t[1-9]"))
	   (goto-char (match-end 0)))
	  (t
	   ;; Move past line number.
	   (skip-chars-forward "[ \t0-9]");From Uli
	   ))
    ;; Move past whitespace.
    (skip-chars-forward " \t")
    (current-column)))

(defun fortran-indent-to-column (col)
  "Indent current line with spaces to column COL.
notes: 1) A non-zero/non-blank character in column 5 indicates a continuation
          line, and this continuation character is retained on indentation;
       2) If `fortran-continuation-string' is the first non-whitespace
          character, this is a continuation line;
       3) A non-continuation line which has a number as the first
          non-whitespace character is a numbered line.
       4) A TAB followed by a digit indicates a continuation line."
  (save-excursion
    (beginning-of-line)
    (if (looking-at comment-line-start-skip)
	(if fortran-comment-indent-style
	    (let ((char (if (stringp fortran-comment-indent-char)
			    (aref fortran-comment-indent-char 0)
			  fortran-comment-indent-char)))
	      (goto-char (match-end 0))
	      (delete-horizontal-regexp (concat " \t" (char-to-string char)))
	      (insert-char char (- col (current-column)))))
      (if (looking-at "\t[1-9]")
	  (if indent-tabs-mode
	      (goto-char (match-end 0))
	    (delete-char 2)
	    (insert "     ")
	    (insert fortran-continuation-string))
	(if (looking-at "     [^ 0\n]")
	    (if indent-tabs-mode
		(progn (delete-char 6)
		       (insert "\t")
		       (insert-char (fortran-numerical-continuation-char) 1))
	      (forward-char 6))
	  (delete-horizontal-space)
	  ;; Put line number in columns 0-4
	  ;; or put continuation character in column 5.
	  (cond ((eobp))
		((looking-at (regexp-quote fortran-continuation-string))
		 (if indent-tabs-mode
		     (progn
		       (indent-to
			(if indent-tabs-mode
			    fortran-minimum-statement-indent-tab
			  fortran-minimum-statement-indent-fixed))
		       (delete-char 1)
		       (insert-char (fortran-numerical-continuation-char) 1))
		   (indent-to 5)
		   (forward-char 1)))
		((looking-at "[0-9]+")
		 (let ((extra-space (- 5 (- (match-end 0) (point)))))
		   (if (< extra-space 0)
		       (message "Warning: line number exceeds 5-digit limit.")
		     (indent-to (min fortran-line-number-indent extra-space))))
		 (skip-chars-forward "0-9")))))
      ;; Point is now after any continuation character or line number.
      ;; Put body of statement where specified.
      (delete-horizontal-space)
      (indent-to col)
      ;; Indent any comment following code on the same line.
      (if (and comment-start-skip
	       (fortran-find-comment-start-skip))
	  (progn (goto-char (match-beginning 0))
		 (if (not (= (current-column) (fortran-comment-hook)))
		     (progn (delete-horizontal-space)
			    (indent-to (fortran-comment-hook)))))))))

(defun fortran-line-number-indented-correctly-p ()
  "Return t if current line's line number is correctly indented.
Do not call if there is no line number."
  (save-excursion
    (beginning-of-line)
    (skip-chars-forward " \t")
    (and (<= (current-column) fortran-line-number-indent)
	 (or (= (current-column) fortran-line-number-indent)
	     (progn (skip-chars-forward "0-9")
		    (= (current-column) 5))))))

(defun fortran-check-for-matching-do ()
  "When called from a numbered statement, return t if matching DO is found.
Otherwise return nil."
  (let (charnum
	(case-fold-search t))
    (save-excursion
      (beginning-of-line)
      (if (looking-at "[ \t]*[0-9]+")
	  (progn
	    (skip-chars-forward " \t")
	    (skip-chars-forward "0") ;skip past leading zeros
	    (setq charnum (buffer-substring (point)
					    (progn (skip-chars-forward "0-9")
						   (point))))
	    (beginning-of-line)
	    (and (re-search-backward
		  (concat "\\(^[ \t0-9]*end\\b[ \t]*[^ \t=(a-z]\\)\\|"
			  "\\(^[ \t0-9]*do[ \t]*0*" charnum "\\b\\)\\|"
			  "\\(^[ \t]*0*" charnum "\\b\\)")
		  nil t)
		 (looking-at (concat "^[ \t0-9]*do[ \t]*0*" charnum))))))))

(defun fortran-find-comment-start-skip ()
  "Move to past `comment-start-skip' found on current line.
Return t if `comment-start-skip' found, nil if not."
;;; In order to move point only if comment-start-skip is found,
;;; this one uses a lot of save-excursions.  Note that re-search-forward
;;; moves point even if comment-start-skip is inside a string-constant.
;;; Some code expects certain values for match-beginning and end
  (interactive)
  (if (save-excursion
	(re-search-forward comment-start-skip
			   (save-excursion (end-of-line) (point)) t))
      (let ((save-match-beginning (match-beginning 0))
	    (save-match-end (match-end 0)))
	(if (fortran-is-in-string-p (match-beginning 0))
	    (save-excursion
	      (goto-char save-match-end)
	      (fortran-find-comment-start-skip)) ; recurse for rest of line
	  (goto-char save-match-beginning)
	  (re-search-forward comment-start-skip
			     (save-excursion (end-of-line) (point)) t)
	  (goto-char (match-end 0))
	  t))
    nil))

;;;From: simon@gnu (Simon Marshall)
;;; Find the next ! not in a string.
(defun fortran-match-!-comment (limit)
  (let (found)
    (while (and (setq found (search-forward "!" limit t))
                (fortran-is-in-string-p (point))))
    (if (not found)
	nil
      ;; Cheaper than `looking-at' "!.*".
      (store-match-data
       (list (1- (point)) (progn (end-of-line) (min (point) limit))))
      t)))

;; The above function is about 10% faster than the below...
;;(defun fortran-match-!-comment (limit)
;;  (let (found)
;;    (while (and (setq found (re-search-forward "!.*" limit t))
;;                (fortran-is-in-string-p (match-beginning 0))))
;;    found))

;;;From: ralf@up3aud1.gwdg.de (Ralf Fassel)
;;; Test if TAB format continuation lines work.
(defun fortran-is-in-string-p (where)
  "Return non-nil iff WHERE (a buffer position) is inside a Fortran string."
  (save-excursion
    (goto-char where)
    (cond
     ((bolp) nil)			; bol is never inside a string
     ((save-excursion			; comment lines too
	(beginning-of-line)(looking-at comment-line-start-skip)) nil)
     (t (let (;; ok, serious now. Init some local vars:
	      (parse-state '(0 nil nil nil nil nil 0))
	      (quoted-comment-start (if comment-start
					(regexp-quote comment-start)))
	      (not-done t)
	      parse-limit
	      end-of-line
	      )
	  ;; move to start of current statement
	  (fortran-next-statement)
	  (fortran-previous-statement)
	  ;; now parse up to WHERE
	  (while not-done
	    (if (or ;; skip to next line if:
		 ;; - comment line?
		 (looking-at comment-line-start-skip)
		 ;; - at end of line?
		 (eolp)
		 ;; - not in a string and after comment-start?
		 (and (not (nth 3 parse-state))
		      comment-start
		      (equal comment-start
			     (char-to-string (preceding-char)))))
		;; get around a bug in forward-line in versions <= 18.57
		(if (or (> (forward-line 1) 0) (eobp))
		    (setq not-done nil))
	      ;; else:
	      ;; if we are at beginning of code line, skip any
	      ;; whitespace, labels and tab continuation markers.
	      (if (bolp) (skip-chars-forward " \t0-9"))
	      ;; if we are in column <= 5 now, check for continuation char
	      (cond ((= 5 (current-column)) (forward-char 1))
		    ((and (< (current-column) 5)
			  (equal fortran-continuation-string
				 (char-to-string (following-char)))
			  (forward-char 1))))
	      ;; find out parse-limit from here
	      (setq end-of-line (save-excursion (end-of-line)(point)))
	      (setq parse-limit (min where end-of-line))
	      ;; parse max up to comment-start, if non-nil and in current line
	      (if comment-start
		  (save-excursion
		    (if (re-search-forward quoted-comment-start end-of-line t)
			(setq parse-limit (min (point) parse-limit)))))
	      ;; now parse if still in limits
	      (if (< (point) where)
		  (setq parse-state (parse-partial-sexp
				     (point) parse-limit nil nil parse-state))
		(setq not-done nil))
	      ))
	  ;; result is
	  (nth 3 parse-state))))))

(defun fortran-auto-fill-mode (arg)
  "Toggle fortran-auto-fill mode.
With ARG, turn `fortran-auto-fill' mode on iff ARG is positive.
In `fortran-auto-fill' mode, inserting a space at a column beyond `fill-column'
automatically breaks the line at a previous space."
  (interactive "P")
  (prog1 (setq auto-fill-function
	       (if (if (null arg)
		       (not auto-fill-function)
		     (> (prefix-numeric-value arg) 0))
		   'fortran-do-auto-fill
		 nil))
    (force-mode-line-update)))

(defun fortran-do-auto-fill ()
  (if (> (current-column) fill-column)
      (fortran-indent-line)))

(defun fortran-fill ()
  (interactive)
  (let* ((opoint (point))
	 (bol (save-excursion (beginning-of-line) (point)))
	 (eol (save-excursion (end-of-line) (point)))
	 (bos (min eol (+ bol (fortran-current-line-indentation))))
	 (quote
	  (save-excursion
	    (goto-char bol)
	    (if (looking-at comment-line-start-skip)
		nil			; OK to break quotes on comment lines.
	      (move-to-column fill-column)
	      (cond ((fortran-is-in-string-p (point))
		     (save-excursion (re-search-backward "[^']'[^']" bol t)
				     (if fortran-break-before-delimiters
					 (point)
				       (1+ (point)))))
		    (t nil)))))
	 ;;
	 ;; decide where to split the line. If a position for a quoted
	 ;; string was found above then use that, else break the line
	 ;; before the last delimiter.
	 ;; Delimiters are whitespace, commas, and operators.
	 ;; Will break before a pair of *'s.
	 ;;
	 (fill-point
	  (or quote
	      (save-excursion
		(move-to-column (1+ fill-column))
		(skip-chars-backward "^ \t\n,'+-/*=)"
;;;		 (if fortran-break-before-delimiters
;;;		     "^ \t\n,'+-/*=" "^ \t\n,'+-/*=)")
		 )
		(if (<= (point) (1+ bos))
		    (progn
		      (move-to-column (1+ fill-column))
;;;what is this doing???
		      (if (not (re-search-forward "[\t\n,'+-/*)=]" eol t))
			  (goto-char bol))))
		(if (bolp)
		    (re-search-forward "[ \t]" opoint t)
		  (forward-char -1)
		  (if (looking-at "'")
		      (forward-char 1)
		    (skip-chars-backward " \t\*")))
		(if fortran-break-before-delimiters
		    (point)
		  (1+ (point))))))
	 )
    ;; if we are in an in-line comment, don't break unless the
    ;; line of code is longer than it should be. Otherwise
    ;; break the line at the column computed above.
    ;;
    ;; Need to use fortran-find-comment-start-skip to make sure that quoted !'s
    ;; don't prevent a break.
    (if (not (or (save-excursion
		   (if (and (re-search-backward comment-start-skip bol t)
			    (not (fortran-is-in-string-p (point))))
		       (progn
			 (skip-chars-backward " \t")
			 (< (current-column) (1+ fill-column)))))
		 (save-excursion
		   (goto-char fill-point)
		   (bolp))))
	(if (> (save-excursion
		 (goto-char fill-point) (current-column))
	       (1+ fill-column))
	    (progn (goto-char fill-point)
		   (fortran-break-line))
	  (save-excursion
	    (if (> (save-excursion
		     (goto-char fill-point)
		     (current-column))
		   (+ (calculate-fortran-indent) fortran-continuation-indent))
		(progn
		  (goto-char fill-point)
		  (fortran-break-line))))))
    ))
(defun fortran-break-line ()
  (let ((opoint (point))
	(bol (save-excursion (beginning-of-line) (point)))
	(eol (save-excursion (end-of-line) (point)))
	(comment-string nil))

    (save-excursion
      (if (and comment-start-skip (fortran-find-comment-start-skip))
	  (progn
	    (re-search-backward comment-start-skip bol t)
	    (setq comment-string (buffer-substring (point) eol))
	    (delete-region (point) eol))))
;;; Forward line 1 really needs to go to next non white line
    (if (save-excursion (forward-line 1)
			(or (looking-at "     [^ 0\n]")
			    (looking-at "\t[1-9]")))
	(progn
	  (end-of-line)
	  (delete-region (point) (match-end 0))
	  (delete-horizontal-space)
	  (fortran-fill))
      (fortran-split-line))
    (if comment-string
	(save-excursion
	  (goto-char bol)
	  (end-of-line)
	  (delete-horizontal-space)
	  (indent-to (fortran-comment-hook))
	  (insert comment-string)))))

(defun fortran-analyze-file-format ()
  "Return nil if fixed format is used, t if TAB formatting is used.
Use `fortran-tab-mode-default' if no non-comment statements are found in the
file before the end or the first `fortran-analyze-depth' lines."
  (let ((i 0))
    (save-excursion
      (goto-char (point-min))
      (setq i 0)
      (while (not (or
		   (eobp)
		   (looking-at "\t")
		   (looking-at "      ")
		   (> i fortran-analyze-depth)))
	(forward-line)
	(setq i (1+ i)))
      (cond
       ((looking-at "\t") t)
       ((looking-at "      ") nil)
       (fortran-tab-mode-default t)
       (t nil)))))

(or (assq 'fortran-tab-mode-string minor-mode-alist)
    (setq minor-mode-alist (cons
			    '(fortran-tab-mode-string
			      (indent-tabs-mode fortran-tab-mode-string))
			    minor-mode-alist)))

(provide 'fortran)

;;; fortran.el ends here