(defvar comint-prompt-regexp)
(defgroup prolog nil
"Major mode for editing and running Prolog under Emacs."
:link '(custom-group-link :tag "Font Lock Faces group" font-lock-faces)
:group 'languages)
(defcustom prolog-program-name
(let ((names '("prolog" "gprolog" "swipl")))
(while (and names
(not (executable-find (car names))))
(setq names (cdr names)))
(or (car names) "prolog"))
"Program name for invoking an inferior Prolog with `run-prolog'."
:type 'string
:group 'prolog)
(defcustom prolog-consult-string "reconsult(user).\n"
"(Re)Consult mode (for C-Prolog and Quintus Prolog). "
:type 'string
:group 'prolog)
(defcustom prolog-compile-string "compile(user).\n"
"Compile mode (for Quintus Prolog)."
:type 'string
:group 'prolog)
(defcustom prolog-eof-string "end_of_file.\n"
"String that represents end of file for Prolog.
When nil, send actual operating system end of file."
:type 'string
:group 'prolog)
(defcustom prolog-indent-width 4
"Level of indentation in Prolog buffers."
:type 'integer
:group 'prolog)
(defvar prolog-font-lock-keywords
'(("\\(#[<=]=>\\|:-\\)\\|\\(#=\\)\\|\\(#[#<>\\/][=\\/]*\\|!\\)"
0 font-lock-keyword-face)
("\\<\\(is\\|write\\|nl\\|read_\\sw+\\)\\>"
1 font-lock-keyword-face)
("^\\(\\sw+\\)\\s-*\\((\\(.+\\))\\)*"
(1 font-lock-function-name-face)
(3 font-lock-variable-name-face)))
"Font-lock keywords for Prolog mode.")
(defvar prolog-mode-syntax-table
(let ((table (make-syntax-table)))
(modify-syntax-entry ?_ "w" table)
(modify-syntax-entry ?\\ "\\" table)
(modify-syntax-entry ?/ ". 14" table)
(modify-syntax-entry ?* ". 23" table)
(modify-syntax-entry ?+ "." table)
(modify-syntax-entry ?- "." table)
(modify-syntax-entry ?= "." table)
(modify-syntax-entry ?% "<" table)
(modify-syntax-entry ?\n ">" table)
(modify-syntax-entry ?< "." table)
(modify-syntax-entry ?> "." table)
(modify-syntax-entry ?\' "\"" table)
table))
(defvar prolog-mode-abbrev-table nil)
(define-abbrev-table 'prolog-mode-abbrev-table ())
(defun prolog-mode-variables ()
(make-local-variable 'paragraph-separate)
(setq paragraph-separate (concat "%%\\|$\\|" page-delimiter)) (make-local-variable 'paragraph-ignore-fill-prefix)
(setq paragraph-ignore-fill-prefix t)
(make-local-variable 'imenu-generic-expression)
(setq imenu-generic-expression '((nil "^\\sw+" 0)))
(make-local-variable 'indent-line-function)
(setq indent-line-function 'prolog-indent-line)
(make-local-variable 'comment-start)
(setq comment-start "%")
(make-local-variable 'comment-start-skip)
(setq comment-start-skip "\\(?:%+\\|/\\*+\\)[ \t]*")
(make-local-variable 'comment-end-skip)
(setq comment-end-skip "[ \t]*\\(\n\\|\\*+/\\)")
(make-local-variable 'comment-column)
(setq comment-column 48))
(defvar prolog-mode-map
(let ((map (make-sparse-keymap)))
(define-key map "\e\C-x" 'prolog-consult-region)
(define-key map "\C-c\C-l" 'inferior-prolog-load-file)
(define-key map "\C-c\C-z" 'switch-to-prolog)
map))
(easy-menu-define prolog-mode-menu prolog-mode-map "Menu for Prolog mode."
'("Prolog"
["Indent line" indent-according-to-mode t]
["Indent region" indent-region t]
["Comment region" comment-region t]
["Uncomment region" uncomment-region t]
"--"
["Run interactive Prolog session" run-prolog t]
))
(defun prolog-mode ()
"Major mode for editing Prolog code for Prologs.
Blank lines and `%%...' separate paragraphs. `%'s start comments.
Commands:
\\{prolog-mode-map}
Entry to this mode calls the value of `prolog-mode-hook'
if that value is non-nil."
(interactive)
(kill-all-local-variables)
(use-local-map prolog-mode-map)
(set-syntax-table prolog-mode-syntax-table)
(setq major-mode 'prolog-mode)
(setq mode-name "Prolog")
(prolog-mode-variables)
(set (make-local-variable 'comment-add) 1)
(setq font-lock-defaults '(prolog-font-lock-keywords
nil nil nil
beginning-of-line))
(run-mode-hooks 'prolog-mode-hook))
(defun prolog-indent-line ()
"Indent current line as Prolog code.
With argument, indent any additional lines of the same clause
rigidly along with this one (not yet)."
(interactive "p")
(let ((indent (prolog-indent-level))
(pos (- (point-max) (point))))
(beginning-of-line)
(indent-line-to indent)
(if (> (- (point-max) pos) (point))
(goto-char (- (point-max) pos)))))
(defun prolog-indent-level ()
"Compute Prolog indentation level."
(save-excursion
(beginning-of-line)
(skip-chars-forward " \t")
(cond
((looking-at "%%%") 0) ((looking-at "%[^%]") comment-column) ((bobp) 0) (t
(let ((empty t) ind more less)
(if (looking-at ")")
(setq less t) (setq less nil))
(while empty
(forward-line -1)
(beginning-of-line)
(if (bobp)
(setq empty nil)
(skip-chars-forward " \t")
(if (not (or (looking-at "%[^%]") (looking-at "\n")))
(setq empty nil))))
(if (bobp)
(setq ind 0) (setq ind (current-column))) (if (looking-at "%%[^%]")
ind
(if (looking-at "(")
(setq more t) (setq more nil))
(end-of-prolog-clause)
(or (bobp) (forward-char -1))
(cond ((looking-at "[,(;>]")
(if (and more (looking-at "[^,]"))
(+ ind prolog-indent-width) (max tab-width ind))) ((looking-at "-") tab-width) ((or less (looking-at "[^.]"))
(max (- ind prolog-indent-width) 0)) (t 0)) )))
)))
(defun end-of-prolog-clause ()
"Go to end of clause in this line."
(beginning-of-line 1)
(let* ((eolpos (save-excursion (end-of-line) (point))))
(if (re-search-forward comment-start-skip eolpos 'move)
(goto-char (match-beginning 0)))
(skip-chars-backward " \t")))
(defvar inferior-prolog-mode-map
(let ((map (make-sparse-keymap)))
(define-key map [remap self-insert-command]
'inferior-prolog-self-insert-command)
map))
(defvar inferior-prolog-mode-syntax-table prolog-mode-syntax-table)
(defvar inferior-prolog-mode-abbrev-table prolog-mode-abbrev-table)
(define-derived-mode inferior-prolog-mode comint-mode "Inferior Prolog"
"Major mode for interacting with an inferior Prolog process.
The following commands are available:
\\{inferior-prolog-mode-map}
Entry to this mode calls the value of `prolog-mode-hook' with no arguments,
if that value is non-nil. Likewise with the value of `comint-mode-hook'.
`prolog-mode-hook' is called after `comint-mode-hook'.
You can send text to the inferior Prolog from other buffers using the commands
`process-send-region', `process-send-string' and \\[prolog-consult-region].
Commands:
Tab indents for Prolog; with argument, shifts rest
of expression rigidly with the current line.
Paragraphs are separated only by blank lines and '%%'.
'%'s start comments.
Return at end of buffer sends line as input.
Return not at end copies rest of line to end and sends it.
\\[comint-kill-input] and \\[backward-kill-word] are kill commands, imitating normal Unix input editing.
\\[comint-interrupt-subjob] interrupts the shell or its current subjob if any.
\\[comint-stop-subjob] stops. \\[comint-quit-subjob] sends quit signal."
(setq comint-prompt-regexp "^| [ ?][- ] *")
(prolog-mode-variables))
(defvar inferior-prolog-buffer nil)
(defun inferior-prolog-run (&optional name)
(with-current-buffer (make-comint "prolog" (or name prolog-program-name))
(inferior-prolog-mode)
(setq-default inferior-prolog-buffer (current-buffer))
(make-local-variable 'inferior-prolog-buffer)
(when (and name (not (equal name prolog-program-name)))
(set (make-local-variable 'prolog-program-name) name))
(set (make-local-variable 'inferior-prolog-flavor)
(let* ((proc (get-buffer-process (current-buffer)))
(pmark (and proc (marker-position (process-mark proc)))))
(cond
((null pmark) (1- (point-min)))
((> pmark (point-min)) (copy-marker (1- pmark)))
(t (1- pmark)))))
(add-hook 'comint-output-filter-functions
'inferior-prolog-guess-flavor nil t)))
(defun inferior-prolog-process (&optional dontstart)
(or (and (buffer-live-p inferior-prolog-buffer)
(get-buffer-process inferior-prolog-buffer))
(unless dontstart
(inferior-prolog-run)
(inferior-prolog-process))))
(defvar inferior-prolog-flavor 'unknown
"Either a symbol or a buffer position offset by one.
If a buffer position, the flavor has not been determined yet and
it is expected that the process's output has been or will
be inserted at that position plus one.")
(defun inferior-prolog-guess-flavor (&optional ignored)
(save-excursion
(goto-char (1+ inferior-prolog-flavor))
(setq inferior-prolog-flavor
(cond
((looking-at "GNU Prolog") 'gnu)
((looking-at "Welcome to SWI-Prolog") 'swi)
((looking-at ".*\n") 'unknown) (t inferior-prolog-flavor))))
(when (symbolp inferior-prolog-flavor)
(remove-hook 'comint-output-filter-functions
'inferior-prolog-guess-flavor t)
(if (eq inferior-prolog-flavor 'gnu)
(set (make-local-variable 'comint-process-echoes) t))))
(defalias 'run-prolog 'switch-to-prolog)
(defun switch-to-prolog (&optional name)
"Run an inferior Prolog process, input and output via buffer *prolog*.
With prefix argument \\[universal-prefix], prompt for the program to use."
(interactive
(list (when current-prefix-arg
(let ((proc (inferior-prolog-process 'dontstart)))
(if proc
(if (yes-or-no-p "Kill current process before starting new one? ")
(kill-process proc)
(error "Abort")))
(read-string "Run Prolog: " prolog-program-name)))))
(unless (inferior-prolog-process 'dontstart)
(inferior-prolog-run name))
(pop-to-buffer inferior-prolog-buffer))
(defun inferior-prolog-self-insert-command ()
"Insert the char in the buffer or pass it directly to the process."
(interactive)
(let* ((proc (get-buffer-process (current-buffer)))
(pmark (and proc (marker-position (process-mark proc)))))
(if (and (eq inferior-prolog-flavor 'gnu)
pmark
(null current-prefix-arg)
(eobp)
(eq (point) pmark)
(save-excursion
(goto-char (- pmark 3))
(looking-at " \\? ")))
(comint-send-string proc (string last-command-char))
(call-interactively 'self-insert-command))))
(defun prolog-consult-region (compile beg end)
"Send the region to the Prolog process made by \"M-x run-prolog\".
If COMPILE (prefix arg) is not nil, use compile mode rather than consult mode."
(interactive "P\nr")
(let ((proc (inferior-prolog-process)))
(comint-send-string proc
(if compile prolog-compile-string
prolog-consult-string))
(comint-send-region proc beg end)
(comint-send-string proc "\n") (if prolog-eof-string
(comint-send-string proc prolog-eof-string)
(with-current-buffer (process-buffer proc)
(comint-send-eof)))))
(defun prolog-consult-region-and-go (compile beg end)
"Send the region to the inferior Prolog, and switch to *prolog* buffer.
If COMPILE (prefix arg) is not nil, use compile mode rather than consult mode."
(interactive "P\nr")
(prolog-consult-region compile beg end)
(pop-to-buffer inferior-prolog-buffer))
(defun inferior-prolog-load-file ()
"Pass the current buffer's file to the inferior prolog process."
(interactive)
(save-buffer)
(let ((file buffer-file-name)
(proc (inferior-prolog-process)))
(with-current-buffer (process-buffer proc)
(comint-send-string proc (concat "['" (file-relative-name file) "'].\n"))
(pop-to-buffer (current-buffer)))))
(provide 'prolog)