icon.el

来自「早期freebsd实现」· EL 代码 · 共 532 行 · 第 1/2 页

    (beginning-of-line)
    (let ((indent-point (point))
	  (case-fold-search nil)
	  state
	  containing-sexp
	  toplevel)
      (if parse-start
	  (goto-char parse-start)
	(setq toplevel (beginning-of-icon-defun)))
      (while (< (point) indent-point)
	(setq parse-start (point))
	(setq state (parse-partial-sexp (point) indent-point 0))
	(setq containing-sexp (car (cdr state))))
      (cond ((or (nth 3 state) (nth 4 state))
	     ;; return nil or t if should not change this line
	     (nth 4 state))
	    ((and containing-sexp
		  (/= (char-after containing-sexp) ?{))
	     ;; line is expression, not statement:
	     ;; indent to just after the surrounding open.
	     (goto-char (1+ containing-sexp))
	     (current-column))
	    (t
	      ;; Statement level.  Is it a continuation or a new statement?
	      ;; Find previous non-comment character.
	      (if toplevel
		  (progn (icon-backward-to-noncomment (point-min))
			 (if (icon-is-continuation-line)
			     icon-continued-statement-offset 0))
		(if (null containing-sexp)
		    (progn (beginning-of-icon-defun)
			   (setq containing-sexp (point))))
		(goto-char indent-point)
		(icon-backward-to-noncomment containing-sexp)
		;; Now we get the answer.
		(if (icon-is-continuation-line)
		    ;; This line is continuation of preceding line's statement;
		    ;; indent  icon-continued-statement-offset  more than the
		    ;; first line of the statement.
		    (progn
		      (icon-backward-to-start-of-continued-exp containing-sexp)
		      (+ icon-continued-statement-offset (current-column)
			 (if (save-excursion (goto-char indent-point)
					     (skip-chars-forward " \t")
					     (eq (following-char) ?{))
			     icon-continued-brace-offset 0)))
		  ;; This line starts a new statement.
		  ;; Position following last unclosed open.
		  (goto-char containing-sexp)
		  ;; Is line first statement after an open-brace?
		  (or
		    ;; If no, find that first statement and indent like it.
		    (save-excursion
		      (if (looking-at "procedure\\s ")
			  (forward-sexp 3)
			(forward-char 1))
		      (while (progn (skip-chars-forward " \t\n")
				    (looking-at "#"))
			;; Skip over comments following openbrace.
			(forward-line 1))
		      ;; The first following code counts
		      ;; if it is before the line we want to indent.
		      (and (< (point) indent-point)
			   (current-column)))
		    ;; If no previous statement,
		    ;; indent it relative to line brace is on.
		    ;; For open brace in column zero, don't let statement
		    ;; start there too.  If icon-indent-level is zero,
		    ;; use icon-brace-offset + icon-continued-statement-offset instead.
		    ;; For open-braces not the first thing in a line,
		    ;; add in icon-brace-imaginary-offset.
		    (+ (if (and (bolp) (zerop icon-indent-level))
			   (+ icon-brace-offset icon-continued-statement-offset)
			 icon-indent-level)
		       ;; Move back over whitespace before the openbrace.
		       ;; If openbrace is not first nonwhite thing on the line,
		       ;; add the icon-brace-imaginary-offset.
		       (progn (skip-chars-backward " \t")
			      (if (bolp) 0 icon-brace-imaginary-offset))
		       ;; here we are
		       (current-indentation))))))))))

(defun icon-is-continuation-line ()
  (let* ((ch (preceding-char))
	 (ch-syntax (char-syntax ch)))
    (if (eq ch-syntax ?w)
	(assoc (buffer-substring
		 (progn (forward-word -1) (point))
		 (progn (forward-word 1) (point)))
	       '(("do") ("dynamic") ("else") ("initial") ("link")
		 ("local") ("of") ("static") ("then")))
      (not (memq ch '(0 ?\; ?\} ?\{ ?\) ?\] ?\" ?\' ?\n))))))

(defun icon-backward-to-noncomment (lim)
  (let (opoint stop)
    (while (not stop)
      (skip-chars-backward " \t\n\f" lim)
      (setq opoint (point))
      (beginning-of-line)
      (if (and (search-forward "#" opoint 'move)
	       (< lim (point)))
	  (forward-char -1)
	(setq stop t)))))

(defun icon-backward-to-start-of-continued-exp (lim)
  (if (memq (preceding-char) '(?\) ?\]))
      (forward-sexp -1))
  (while (icon-is-continued-line)
    (end-of-line 0))
  (beginning-of-line)
  (if (<= (point) lim)
      (goto-char (1+ lim)))
  (skip-chars-forward " \t"))

(defun icon-is-continued-line ()
  (save-excursion
    (end-of-line 0)
    (icon-is-continuation-line)))

(defun icon-backward-to-start-of-if (&optional limit)
  "Move to the start of the last ``unbalanced'' if."
  (or limit (setq limit (save-excursion (beginning-of-icon-defun) (point))))
  (let ((if-level 1)
	(case-fold-search nil))
    (while (not (zerop if-level))
      (backward-sexp 1)
      (cond ((looking-at "else\\b")
	     (setq if-level (1+ if-level)))
	    ((looking-at "if\\b")
	     (setq if-level (1- if-level)))
	    ((< (point) limit)
	     (setq if-level 0)
	     (goto-char limit))))))

(defun mark-icon-function ()
  "Put mark at end of Icon function, point at beginning."
  (interactive)
  (push-mark (point))
  (end-of-icon-defun)
  (push-mark (point))
  (beginning-of-line 0)
  (beginning-of-icon-defun))

(defun beginning-of-icon-defun ()
  "Go to the start of the enclosing procedure; return t if at top level."
  (interactive)
  (if (re-search-backward "^procedure\\s \\|^end[ \t\n]" (point-min) 'move)
      (looking-at "e")
    t))

(defun end-of-icon-defun ()
  (interactive)
  (if (not (bobp)) (forward-char -1))
  (re-search-forward "\\(\\s \\|^\\)end\\(\\s \\|$\\)" (point-max) 'move)
  (forward-word -1)
  (forward-line 1))

(defun indent-icon-exp ()
  "Indent each line of the Icon grouping following point."
  (interactive)
  (let ((indent-stack (list nil))
	(contain-stack (list (point)))
	(case-fold-search nil)
	restart outer-loop-done inner-loop-done state ostate
	this-indent last-sexp
	at-else at-brace at-do
	(opoint (point))
	(next-depth 0))
    (save-excursion
      (forward-sexp 1))
    (save-excursion
      (setq outer-loop-done nil)
      (while (and (not (eobp)) (not outer-loop-done))
	(setq last-depth next-depth)
	;; Compute how depth changes over this line
	;; plus enough other lines to get to one that
	;; does not end inside a comment or string.
	;; Meanwhile, do appropriate indentation on comment lines.
	(setq innerloop-done nil)
	(while (and (not innerloop-done)
		    (not (and (eobp) (setq outer-loop-done t))))
	  (setq ostate state)
	  (setq state (parse-partial-sexp (point) (progn (end-of-line) (point))
					  nil nil state))
	  (setq next-depth (car state))
	  (if (and (car (cdr (cdr state)))
		   (>= (car (cdr (cdr state))) 0))
	      (setq last-sexp (car (cdr (cdr state)))))
	  (if (or (nth 4 ostate))
	      (icon-indent-line))
	  (if (or (nth 3 state))
	      (forward-line 1)
	    (setq innerloop-done t)))
	(if (<= next-depth 0)
	    (setq outer-loop-done t))
	(if outer-loop-done
	    nil
	  (if (/= last-depth next-depth)
	      (setq last-sexp nil))
	  (while (> last-depth next-depth)
	    (setq indent-stack (cdr indent-stack)
		  contain-stack (cdr contain-stack)
		  last-depth (1- last-depth)))
	  (while (< last-depth next-depth)
	    (setq indent-stack (cons nil indent-stack)
		  contain-stack (cons nil contain-stack)
		  last-depth (1+ last-depth)))
	  (if (null (car contain-stack))
	      (setcar contain-stack (or (car (cdr state))
					(save-excursion (forward-sexp -1)
							(point)))))
	  (forward-line 1)
	  (skip-chars-forward " \t")
	  (if (eolp)
	      nil
	    (if (and (car indent-stack)
		     (>= (car indent-stack) 0))
		;; Line is on an existing nesting level.
		;; Lines inside parens are handled specially.
		(if (/= (char-after (car contain-stack)) ?{)
		    (setq this-indent (car indent-stack))
		  ;; Line is at statement level.
		  ;; Is it a new statement?  Is it an else?
		  ;; Find last non-comment character before this line
		  (save-excursion
		    (setq at-else (looking-at "else\\W"))
		    (setq at-brace (= (following-char) ?{))
		    (icon-backward-to-noncomment opoint)
		    (if (icon-is-continuation-line)
			;; Preceding line did not end in comma or semi;
			;; indent this line  icon-continued-statement-offset
			;; more than previous.
			(progn
			  (icon-backward-to-start-of-continued-exp (car contain-stack))
			  (setq this-indent
				(+ icon-continued-statement-offset (current-column)
				   (if at-brace icon-continued-brace-offset 0))))
		      ;; Preceding line ended in comma or semi;
		      ;; use the standard indent for this level.
		      (if at-else
			  (progn (icon-backward-to-start-of-if opoint)
				 (setq this-indent (current-indentation)))
			(setq this-indent (car indent-stack))))))
	      ;; Just started a new nesting level.
	      ;; Compute the standard indent for this level.
	      (let ((val (calculate-icon-indent
			   (if (car indent-stack)
			       (- (car indent-stack))))))
		(setcar indent-stack
			(setq this-indent val))))
	    ;; Adjust line indentation according to its contents
	    (if (or (= (following-char) ?})
		    (looking-at "end\\b"))
		(setq this-indent (- this-indent icon-indent-level)))
	    (if (= (following-char) ?{)
		(setq this-indent (+ this-indent icon-brace-offset)))
	    ;; Put chosen indentation into effect.
	    (or (= (current-column) this-indent)
		(progn
		  (delete-region (point) (progn (beginning-of-line) (point)))
		  (indent-to this-indent)))
	    ;; Indent any comment following the text.
	    (or (looking-at comment-start-skip)
		(if (re-search-forward comment-start-skip (save-excursion (end-of-line) (point)) t)
		    (progn (indent-for-comment) (beginning-of-line))))))))))