lisp/progmodes/prolog.el

   1 ;;; prolog.el --- major mode for editing and running Prolog under Emacs
   2
   3 ;; Copyright (C) 1986, 1987 Free Software Foundation, Inc.
   4
   5 ;; Author: Masanobu UMEDA <umerin@flab.flab.fujitsu.junet>
   6 ;; Keywords: languages
   7
   8 ;; This file is part of GNU Emacs.
   9
  10 ;; GNU Emacs is free software; you can redistribute it and/or modify
  11 ;; it under the terms of the GNU General Public License as published by
  12 ;; the Free Software Foundation; either version 2, or (at your option)
  13 ;; any later version.
  14
  15 ;; GNU Emacs is distributed in the hope that it will be useful,
  16 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  17 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18 ;; GNU General Public License for more details.
  19
  20 ;; You should have received a copy of the GNU General Public License
  21 ;; along with GNU Emacs; see the file COPYING.  If not, write to
  22 ;; the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
  23
  24 ;;; Commentary:
  25
  26 ;; This package provides a major mode for editing Prolog.  It knows
  27 ;; about Prolog syntax and comments, and can send regions to an inferior
  28 ;; Prolog interpreter process.
  29
  30 ;;; Code:
  31
  32 (defvar prolog-mode-syntax-table nil)
  33 (defvar prolog-mode-abbrev-table nil)
  34 (defvar prolog-mode-map nil)
  35
  36 (defvar prolog-program-name "prolog"
  37   "*Program name for invoking an inferior Prolog with `run-prolog'.")
  38
  39 (defvar prolog-consult-string "reconsult(user).\n"
  40   "*(Re)Consult mode (for C-Prolog and Quintus Prolog). ")
  41
  42 (defvar prolog-compile-string "compile(user).\n"
  43   "*Compile mode (for Quintus Prolog).")
  44
  45 (defvar prolog-eof-string "end_of_file.\n"
  46   "*String that represents end of file for prolog.
  47 nil means send actual operating system end of file.")
  48
  49 (defvar prolog-indent-width 4)
  50
  51 (if prolog-mode-syntax-table
  52     ()
  53   (let ((table (make-syntax-table)))
  54     (modify-syntax-entry ?_ "w" table)
  55     (modify-syntax-entry ?\\ "\\" table)
  56     (modify-syntax-entry ?/ "." table)
  57     (modify-syntax-entry ?* "." table)
  58     (modify-syntax-entry ?+ "." table)
  59     (modify-syntax-entry ?- "." table)
  60     (modify-syntax-entry ?= "." table)
  61     (modify-syntax-entry ?% "<" table)
  62     (modify-syntax-entry ?\n ">" table)
  63     (modify-syntax-entry ?< "." table)
  64     (modify-syntax-entry ?> "." table)
  65     (modify-syntax-entry ?\' "\"" table)
  66     (setq prolog-mode-syntax-table table)))
  67
  68 (define-abbrev-table 'prolog-mode-abbrev-table ())
  69
  70 (defun prolog-mode-variables ()
  71   (set-syntax-table prolog-mode-syntax-table)
  72   (setq local-abbrev-table prolog-mode-abbrev-table)
  73   (make-local-variable 'paragraph-start)
  74   (setq paragraph-start (concat "^%%\\|^$\\|" page-delimiter)) ;'%%..'
  75   (make-local-variable 'paragraph-separate)
  76   (setq paragraph-separate paragraph-start)
  77   (make-local-variable 'paragraph-ignore-fill-prefix)
  78   (setq paragraph-ignore-fill-prefix t)
  79   (make-local-variable 'indent-line-function)
  80   (setq indent-line-function 'prolog-indent-line)
  81   (make-local-variable 'comment-start)
  82   (setq comment-start "%")
  83   (make-local-variable 'comment-start-skip)
  84   (setq comment-start-skip "%+ *")
  85   (make-local-variable 'comment-column)
  86   (setq comment-column 48)
  87   (make-local-variable 'comment-indent-function)
  88   (setq comment-indent-function 'prolog-comment-indent))
  89
  90 (defun prolog-mode-commands (map)
  91   (define-key map "\t" 'prolog-indent-line)
  92   (define-key map "\e\C-x" 'prolog-consult-region))
  93
  94 (if prolog-mode-map
  95     nil
  96   (setq prolog-mode-map (make-sparse-keymap))
  97   (prolog-mode-commands prolog-mode-map))
  98
  99 ;;;###autoload
 100 (defun prolog-mode ()
 101   "Major mode for editing Prolog code for Prologs.
 102 Blank lines and `%%...' separate paragraphs.  `%'s start comments.
 103 Commands:
 104 \\{prolog-mode-map}
 105 Entry to this mode calls the value of `prolog-mode-hook'
 106 if that value is non-nil."
 107   (interactive)
 108   (kill-all-local-variables)
 109   (use-local-map prolog-mode-map)
 110   (setq major-mode 'prolog-mode)
 111   (setq mode-name "Prolog")
 112   (prolog-mode-variables)
 113   (run-hooks 'prolog-mode-hook))
 114
 115 (defun prolog-indent-line (&optional whole-exp)
 116   "Indent current line as Prolog code.
 117 With argument, indent any additional lines of the same clause
 118 rigidly along with this one (not yet)."
 119   (interactive "p")
 120   (let ((indent (prolog-indent-level))
 121         (pos (- (point-max) (point))) beg)
 122     (beginning-of-line)
 123     (setq beg (point))
 124     (skip-chars-forward " \t")
 125     (if (zerop (- indent (current-column)))
 126         nil
 127       (delete-region beg (point))
 128       (indent-to indent))
 129     (if (> (- (point-max) pos) (point))
 130         (goto-char (- (point-max) pos)))
 131     ))
 132
 133 (defun prolog-indent-level ()
 134   "Compute prolog indentation level."
 135   (save-excursion
 136     (beginning-of-line)
 137     (skip-chars-forward " \t")
 138     (cond
 139      ((looking-at "%%%") 0)             ;Large comment starts
 140      ((looking-at "%[^%]") comment-column) ;Small comment starts
 141      ((bobp) 0)                         ;Beginning of buffer
 142      (t
 143       (let ((empty t) ind more less)
 144         (if (looking-at ")")
 145             (setq less t)               ;Find close
 146           (setq less nil))
 147         ;; See previous indentation
 148         (while empty
 149           (forward-line -1)
 150           (beginning-of-line)
 151           (if (bobp)
 152               (setq empty nil)
 153             (skip-chars-forward " \t")
 154             (if (not (or (looking-at "%[^%]") (looking-at "\n")))
 155                 (setq empty nil))))
 156         (if (bobp)
 157             (setq ind 0)                ;Beginning of buffer
 158           (setq ind (current-column)))  ;Beginning of clause
 159         ;; See its beginning
 160         (if (looking-at "%%[^%]")
 161             ind
 162           ;; Real prolog code
 163           (if (looking-at "(")
 164               (setq more t)             ;Find open
 165             (setq more nil))
 166           ;; See its tail
 167           (end-of-prolog-clause)
 168           (or (bobp) (forward-char -1))
 169           (cond ((looking-at "[,(;>]")
 170                  (if (and more (looking-at "[^,]"))
 171                      (+ ind prolog-indent-width) ;More indentation
 172                    (max tab-width ind))) ;Same indentation
 173                 ((looking-at "-") tab-width) ;TAB
 174                 ((or less (looking-at "[^.]"))
 175                  (max (- ind prolog-indent-width) 0)) ;Less indentation
 176                 (t 0))                  ;No indentation
 177           )))
 178      )))
 179
 180 (defun end-of-prolog-clause ()
 181   "Go to end of clause in this line."
 182   (beginning-of-line 1)
 183   (let* ((eolpos (save-excursion (end-of-line) (point))))
 184     (if (re-search-forward comment-start-skip eolpos 'move)
 185         (goto-char (match-beginning 0)))
 186     (skip-chars-backward " \t")))
 187
 188 (defun prolog-comment-indent ()
 189   "Compute prolog comment indentation."
 190   (cond ((looking-at "%%%") 0)
 191         ((looking-at "%%") (prolog-indent-level))
 192         (t
 193          (save-excursion
 194                (skip-chars-backward " \t")
 195                ;; Insert one space at least, except at left margin.
 196                (max (+ (current-column) (if (bolp) 0 1))
 197                     comment-column)))
 198         ))
 199
 200 \f
 201 ;;;
 202 ;;; Inferior prolog mode
 203 ;;;
 204 (defvar inferior-prolog-mode-map nil)
 205
 206 (defun inferior-prolog-mode ()
 207   "Major mode for interacting with an inferior Prolog process.
 208
 209 The following commands are available:
 210 \\{inferior-prolog-mode-map}
 211
 212 Entry to this mode calls the value of `prolog-mode-hook' with no arguments,
 213 if that value is non-nil.  Likewise with the value of `comint-mode-hook'.
 214 `prolog-mode-hook' is called after `comint-mode-hook'.
 215
 216 You can send text to the inferior Prolog from other buffers
 217 using the commands `send-region', `send-string' and \\[prolog-consult-region].
 218
 219 Commands:
 220 Tab indents for Prolog; with argument, shifts rest
 221  of expression rigidly with the current line.
 222 Paragraphs are separated only by blank lines and '%%'.
 223 '%'s start comments.
 224
 225 Return at end of buffer sends line as input.
 226 Return not at end copies rest of line to end and sends it.
 227 \\[comint-kill-input] and \\[backward-kill-word] are kill commands, imitating normal Unix input editing.
 228 \\[comint-interrupt-subjob] interrupts the shell or its current subjob if any.
 229 \\[comint-stop-subjob] stops. \\[comint-quit-subjob] sends quit signal."
 230   (interactive)
 231   (require 'comint)
 232   (comint-mode)
 233   (setq major-mode 'inferior-prolog-mode
 234         mode-name "Inferior Prolog"
 235         comint-prompt-regexp "^| [ ?][- ] *")
 236   (prolog-mode-variables)
 237   (if inferior-prolog-mode-map nil
 238     (setq inferior-prolog-mode-map (copy-keymap comint-mode-map))
 239     (prolog-mode-commands inferior-prolog-mode-map))
 240   (use-local-map inferior-prolog-mode-map)
 241   (run-hooks 'prolog-mode-hook))
 242
 243 ;;;###autoload
 244 (defun run-prolog ()
 245   "Run an inferior Prolog process, input and output via buffer *prolog*."
 246   (interactive)
 247   (require 'comint)
 248   (switch-to-buffer (make-comint "prolog" prolog-program-name))
 249   (inferior-prolog-mode))
 250
 251 (defun prolog-consult-region (compile beg end)
 252   "Send the region to the Prolog process made by \"M-x run-prolog\".
 253 If COMPILE (prefix arg) is not nil, use compile mode rather than consult mode."
 254   (interactive "P\nr")
 255   (save-excursion
 256     (if compile
 257         (send-string "prolog" prolog-compile-string)
 258       (send-string "prolog" prolog-consult-string))
 259     (send-region "prolog" beg end)
 260     (send-string "prolog" "\n")         ;May be unnecessary
 261     (if prolog-eof-string
 262         (send-string "prolog" prolog-eof-string)
 263       (process-send-eof "prolog")))) ;Send eof to prolog process.
 264
 265 (defun prolog-consult-region-and-go (compile beg end)
 266   "Send the region to the inferior Prolog, and switch to *prolog* buffer.
 267 If COMPILE (prefix arg) is not nil, use compile mode rather than consult mode."
 268   (interactive "P\nr")
 269   (prolog-consult-region compile beg end)
 270   (switch-to-buffer "*prolog*"))
 271
 272 ;;; prolog.el ends here