;;; indent.el --- indentation commands for Emacs
-;; Copyright (C) 1985 Free Software Foundation, Inc.
+;; Copyright (C) 1985, 1995, 2001 Free Software Foundation, Inc.
;; Maintainer: FSF
;; GNU General Public License for more details.
;; You should have received a copy of the GNU General Public License
-;; along with GNU Emacs; see the file COPYING. If not, write to
-;; the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
+;; 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:
+
+;; Commands for making and changing indentation in text. These are
+;; described in the Emacs manual.
;;; Code:
-(defvar indent-line-function 'indent-to-left-margin "\
-Function to indent current line.");Now in loaddefs.el
+(defgroup indent nil
+ "Indentation commands"
+ :group 'editing)
-(defun indent-according-to-mode ()
- "Indent line in proper way for current major mode."
- (interactive)
- (funcall indent-line-function))
+(defcustom standard-indent 4
+ "*Default number of columns for margin-changing functions to indent."
+ :group 'indent
+ :type 'integer)
+
+(defvar indent-line-function 'indent-relative
+ "Function to indent the current line.
+This function will be called with no arguments.
+If it is called somewhere where auto-indentation cannot be done
+\(f.ex. inside a string), the function should simply return `noindent'.
+Setting this function is all you need to make TAB indent appropriately.
+Don't rebind TAB unless you really need to.")
+
+(defcustom tab-always-indent t
+ "*Controls the operation of the TAB key.
+If t, hitting TAB always just indents the current line.
+If nil, hitting TAB indents the current line if point is at the left margin
+ or in the line's indentation, otherwise it insert a \"real\" tab character."
+ :group 'indent
+ :type '(choice (const nil) (const t) (const always)))
-(defun indent-for-tab-command ()
- "Indent line in proper way for current major mode."
+(defun indent-according-to-mode ()
+ "Indent line in proper way for current major mode.
+The buffer-local variable `indent-line-function' determines how to do this,
+but the functions `indent-relative' and `indent-relative-maybe' are
+special; we don't actually use them here."
(interactive)
- (if (eq indent-line-function 'indent-to-left-margin)
- (insert-tab)
+ (if (memq indent-line-function
+ '(indent-relative indent-relative-maybe))
+ ;; These functions are used for tabbing, but can't be used for
+ ;; indenting. Replace with something ad-hoc.
+ (let ((column (save-excursion
+ (beginning-of-line)
+ (skip-chars-backward "\n \t")
+ (beginning-of-line)
+ (current-indentation))))
+ (if (<= (current-column) (current-indentation))
+ (indent-line-to column)
+ (save-excursion (indent-line-to column))))
+ ;; The normal case.
(funcall indent-line-function)))
-(defun insert-tab ()
- (if abbrev-mode
- (expand-abbrev))
- (if indent-tabs-mode
- (insert ?\t)
- (indent-to (* tab-width (1+ (/ (current-column) tab-width))))))
+(defun indent-for-tab-command (&optional arg)
+ "Indent line in proper way for current major mode or insert a tab.
+Depending on `tab-always-indent', either insert a tab or indent.
+If initial point was within line's indentation, position after
+the indentation. Else stay at same point in text.
+The function actually called to indent is determined by the value of
+`indent-line-function'."
+ (interactive "P")
+ (cond
+ ((or ;; indent-to-left-margin is only meant for indenting,
+ ;; so we force it to always insert a tab here.
+ (eq indent-line-function 'indent-to-left-margin)
+ (and (not tab-always-indent)
+ (or (> (current-column) (current-indentation))
+ (eq this-command last-command))))
+ (insert-tab arg))
+ ;; Those functions are meant specifically for tabbing and not for
+ ;; indenting, so we can't pass them to indent-according-to-mode.
+ ((memq indent-line-function '(indent-relative indent-relative-maybe))
+ (funcall indent-line-function))
+ (t ;; The normal case.
+ (indent-according-to-mode))))
+
+(defun insert-tab (&optional arg)
+ (let ((count (prefix-numeric-value arg)))
+ (if (and abbrev-mode
+ (eq (char-syntax (preceding-char)) ?w))
+ (expand-abbrev))
+ (if indent-tabs-mode
+ (insert-char ?\t count)
+ (indent-to (* tab-width (+ count (/ (current-column) tab-width)))))))
(defun indent-rigidly (start end arg)
"Indent all lines starting in the region sideways by ARG columns.
-Called from a program, takes three arguments, START, END and ARG."
+Called from a program, takes three arguments, START, END and ARG.
+You can remove all indentation from a region by giving a large negative ARG."
(interactive "r\np")
(save-excursion
(goto-char end)
(goto-char start)
(or (bolp) (forward-line 1))
(while (< (point) end)
- (let ((indent (current-indentation)))
- (delete-region (point) (progn (skip-chars-forward " \t") (point)))
- (or (eolp)
- (indent-to (max 0 (+ indent arg)) 0)))
+ (let ((indent (current-indentation))
+ eol-flag)
+ (save-excursion
+ (skip-chars-forward " \t")
+ (setq eol-flag (eolp)))
+ (or eol-flag
+ (indent-to (max 0 (+ indent arg)) 0))
+ (delete-region (point) (progn (skip-chars-forward " \t") (point))))
(forward-line 1))
(move-marker end nil)))
-;; This is the default indent-line-function,
+(defun indent-line-to (column)
+ "Indent current line to COLUMN.
+This function removes or adds spaces and tabs at beginning of line
+only if necessary. It leaves point at end of indentation."
+ (back-to-indentation)
+ (let ((cur-col (current-column)))
+ (cond ((< cur-col column)
+ (if (>= (- column (* (/ cur-col tab-width) tab-width)) tab-width)
+ (delete-region (point)
+ (progn (skip-chars-backward " ") (point))))
+ (indent-to column))
+ ((> cur-col column) ; too far right (after tab?)
+ (delete-region (progn (move-to-column column t) (point))
+ (progn (back-to-indentation) (point)))))))
+
+(defun current-left-margin ()
+ "Return the left margin to use for this line.
+This is the value of the buffer-local variable `left-margin' plus the value
+of the `left-margin' text-property at the start of the line."
+ (save-excursion
+ (back-to-indentation)
+ (max 0
+ (+ left-margin (or (get-text-property
+ (if (and (eobp) (not (bobp)))
+ (1- (point)) (point))
+ 'left-margin) 0)))))
+
+(defun move-to-left-margin (&optional n force)
+ "Move to the left margin of the current line.
+With optional argument, move forward N-1 lines first.
+The column moved to is the one given by the `current-left-margin' function.
+If the line's indentation appears to be wrong, and this command is called
+interactively or with optional argument FORCE, it will be fixed."
+ (interactive (list (prefix-numeric-value current-prefix-arg) t))
+ (beginning-of-line n)
+ (skip-chars-forward " \t")
+ (let ((lm (current-left-margin))
+ (cc (current-column)))
+ (cond ((> cc lm)
+ (if (> (move-to-column lm force) lm)
+ ;; If lm is in a tab and we are not forcing, move before tab
+ (backward-char 1)))
+ ((and force (< cc lm))
+ (indent-to-left-margin)))))
+
+;; This used to be the default indent-line-function,
;; used in Fundamental Mode, Text Mode, etc.
(defun indent-to-left-margin ()
- (or (= (current-indentation) left-margin)
- (let (epos)
- (save-excursion
- (beginning-of-line)
- (delete-region (point)
- (progn (skip-chars-forward " \t")
- (point)))
- (indent-to left-margin)
- (setq epos (point)))
- (if (< (point) epos)
- (goto-char epos)))))
+ "Indent current line to the column given by `current-left-margin'."
+ (indent-line-to (current-left-margin)))
+
+(defun delete-to-left-margin (&optional from to)
+ "Remove left margin indentation from a region.
+This deletes to the column given by `current-left-margin'.
+In no case will it delete non-whitespace.
+Args FROM and TO are optional; default is the whole buffer."
+ (save-excursion
+ (goto-char (or to (point-max)))
+ (setq to (point-marker))
+ (goto-char (or from (point-min)))
+ (or (bolp) (forward-line 1))
+ (while (< (point) to)
+ (delete-region (point) (progn (move-to-left-margin nil t) (point)))
+ (forward-line 1))
+ (move-marker to nil)))
+
+(defun set-left-margin (from to lm)
+ "Set the left margin of the region to WIDTH.
+If `auto-fill-mode' is active, re-fill the region to fit the new margin."
+ (interactive "r\nNSet left margin to column: ")
+ (if (interactive-p) (setq lm (prefix-numeric-value lm)))
+ (save-excursion
+ ;; If inside indentation, start from BOL.
+ (goto-char from)
+ (skip-chars-backward " \t")
+ (if (bolp) (setq from (point)))
+ ;; Place end after whitespace
+ (goto-char to)
+ (skip-chars-forward " \t")
+ (setq to (point-marker)))
+ ;; Delete margin indentation first, but keep paragraph indentation.
+ (delete-to-left-margin from to)
+ (put-text-property from to 'left-margin lm)
+ (indent-rigidly from to lm)
+ (if auto-fill-function (save-excursion (fill-region from to nil t t)))
+ (move-marker to nil))
+
+(defun set-right-margin (from to lm)
+ "Set the right margin of the region to WIDTH.
+If `auto-fill-mode' is active, re-fill the region to fit the new margin."
+ (interactive "r\nNSet right margin to width: ")
+ (if (interactive-p) (setq lm (prefix-numeric-value lm)))
+ (save-excursion
+ (goto-char from)
+ (skip-chars-backward " \t")
+ (if (bolp) (setq from (point))))
+ (put-text-property from to 'right-margin lm)
+ (if auto-fill-function (save-excursion (fill-region from to nil t t))))
+
+(defun alter-text-property (from to prop func &optional object)
+ "Programmatically change value of a text-property.
+For each region between FROM and TO that has a single value for PROPERTY,
+apply FUNCTION to that value and sets the property to the function's result.
+Optional fifth argument OBJECT specifies the string or buffer to operate on."
+ (let ((begin from)
+ end val)
+ (while (setq val (get-text-property begin prop object)
+ end (text-property-not-all begin to prop val object))
+ (put-text-property begin end prop (funcall func val) object)
+ (setq begin end))
+ (if (< begin to)
+ (put-text-property begin to prop (funcall func val) object))))
+
+(defun increase-left-margin (from to inc)
+ "Increase or decrease the left-margin of the region.
+With no prefix argument, this adds `standard-indent' of indentation.
+A prefix arg (optional third arg INC noninteractively) specifies the amount
+to change the margin by, in characters.
+If `auto-fill-mode' is active, re-fill the region to fit the new margin."
+ (interactive "*r\nP")
+ (setq inc (if inc (prefix-numeric-value inc) standard-indent))
+ (save-excursion
+ (goto-char from)
+ (skip-chars-backward " \t")
+ (if (bolp) (setq from (point)))
+ (goto-char to)
+ (setq to (point-marker)))
+ (alter-text-property from to 'left-margin
+ (lambda (v) (max (- left-margin) (+ inc (or v 0)))))
+ (indent-rigidly from to inc)
+ (if auto-fill-function (save-excursion (fill-region from to nil t t)))
+ (move-marker to nil))
+
+(defun decrease-left-margin (from to inc)
+ "Make the left margin of the region smaller.
+With no prefix argument, decrease the indentation by `standard-indent'.
+A prefix arg (optional third arg INC noninteractively) specifies the amount
+to change the margin by, in characters.
+If `auto-fill-mode' is active, re-fill the region to fit the new margin."
+ (interactive "*r\nP")
+ (setq inc (if inc (prefix-numeric-value inc) standard-indent))
+ (increase-left-margin from to (- inc)))
+
+(defun increase-right-margin (from to inc)
+ "Increase the right-margin of the region.
+With no prefix argument, increase the right margin by `standard-indent'.
+A prefix arg (optional third arg INC noninteractively) specifies the amount
+to change the margin by, in characters. A negative argument decreases
+the right margin width.
+If `auto-fill-mode' is active, re-fill the region to fit the new margin."
+ (interactive "r\nP")
+ (if (interactive-p)
+ (setq inc (if inc (prefix-numeric-value current-prefix-arg)
+ standard-indent)))
+ (save-excursion
+ (alter-text-property from to 'right-margin
+ (lambda (v) (+ inc (or v 0))))
+ (if auto-fill-function
+ (fill-region from to nil t t))))
+
+(defun decrease-right-margin (from to inc)
+ "Make the right margin of the region smaller.
+With no prefix argument, decrease the right margin by `standard-indent'.
+A prefix arg (optional third arg INC noninteractively) specifies the amount
+of width to remove, in characters. A negative argument increases
+the right margin width.
+If `auto-fill-mode' is active, re-fills region to fit in new margin."
+ (interactive "*r\nP")
+ (setq inc (if inc (prefix-numeric-value inc) standard-indent))
+ (increase-right-margin from to (- inc)))
+
+(defun beginning-of-line-text (&optional n)
+ "Move to the beginning of the text on this line.
+With optional argument, move forward N-1 lines first.
+From the beginning of the line, moves past the left-margin indentation, the
+fill-prefix, and any indentation used for centering or right-justifying the
+line, but does not move past any whitespace that was explicitly inserted
+\(such as a tab used to indent the first line of a paragraph)."
+ (interactive "p")
+ (beginning-of-line n)
+ (skip-chars-forward " \t")
+ ;; Skip over fill-prefix.
+ (if (and fill-prefix
+ (not (string-equal fill-prefix "")))
+ (if (equal fill-prefix
+ (buffer-substring
+ (point) (min (point-max) (+ (length fill-prefix) (point)))))
+ (forward-char (length fill-prefix)))
+ (if (and adaptive-fill-mode adaptive-fill-regexp
+ (looking-at adaptive-fill-regexp))
+ (goto-char (match-end 0))))
+ ;; Skip centering or flushright indentation
+ (if (memq (current-justification) '(center right))
+ (skip-chars-forward " \t")))
(defvar indent-region-function nil
- "Function which is short cut to indent each line in region with TAB.
-A value of nil means really perform TAB on each line.")
+ "Short cut function to indent region using `indent-according-to-mode'.
+A value of nil means really run `indent-according-to-mode' on each line.")
-(defun indent-region (start end arg)
+(defun indent-region (start end &optional column)
"Indent each nonblank line in the region.
-With no argument, indent each line with TAB.
-\(If there is a fill prefix, make each line start with the fill prefix.)
-With argument COLUMN, indent each line to that column.
-Called from a program, takes three args: START, END and COLUMN."
+A numeric prefix argument specifies a column: indent each line to that column.
+
+With no prefix argument, the command chooses one of these methods and
+indents all the lines with it:
+
+ 1) If `fill-prefix' is non-nil, insert `fill-prefix' at the
+ beginning of each line in the region that does not already begin
+ with it.
+ 2) If `indent-region-function' is non-nil, call that function
+ to indent the region.
+ 3) Indent each line as specified by the variable `indent-line-function'.
+
+Called from a program, START and END specify the region to indent.
+If the third argument COLUMN is an integer, it specifies the
+column to indent to; if it is nil, use one of the three methods above."
(interactive "r\nP")
- (if (null arg)
+ (if (null column)
(if fill-prefix
(save-excursion
(goto-char end)
(setq end (point-marker))
(goto-char start)
(let ((regexp (regexp-quote fill-prefix)))
- (while (< (point) end)
- (or (looking-at regexp)
- (insert fill-prefix))
- (forward-line 1))))
+ (while (< (point) end)
+ (or (looking-at regexp)
+ (and (bolp) (eolp))
+ (insert fill-prefix))
+ (forward-line 1))))
(if indent-region-function
(funcall indent-region-function start end)
(save-excursion
- (goto-char end)
- (setq end (point-marker))
- (goto-char start)
- (or (bolp) (forward-line 1))
- (while (< (point) end)
- (funcall indent-line-function)
- (forward-line 1))
- (move-marker end nil))))
- (setq arg (prefix-numeric-value arg))
+ (setq end (copy-marker end))
+ (goto-char start)
+ (while (< (point) end)
+ (or (and (bolp) (eolp))
+ (funcall indent-line-function))
+ (forward-line 1))
+ (move-marker end nil))))
+ (setq column (prefix-numeric-value column))
(save-excursion
(goto-char end)
(setq end (point-marker))
(while (< (point) end)
(delete-region (point) (progn (skip-chars-forward " \t") (point)))
(or (eolp)
- (indent-to arg 0))
+ (indent-to column 0))
(forward-line 1))
(move-marker end nil))))
(defun indent-relative-maybe ()
- "Indent a new line like previous nonblank line."
+ "Indent a new line like previous nonblank line.
+If the previous nonblank line has no indent points beyond the
+column point starts at, this command does nothing.
+
+See also `indent-relative'."
(interactive)
(indent-relative t))
(defun indent-relative (&optional unindented-ok)
"Space out to under next indent point in previous nonblank line.
An indent point is a non-whitespace character following whitespace.
+The following line shows the indentation points in this line.
+ ^ ^ ^ ^ ^ ^ ^ ^ ^
If the previous nonblank line has no indent points beyond the
-column point starts at, `tab-to-tab-stop' is done instead."
+column point starts at, `tab-to-tab-stop' is done instead, unless
+this command is invoked with a numeric argument, in which case it
+does nothing.
+
+See also `indent-relative-maybe'."
(interactive "P")
- (if abbrev-mode (expand-abbrev))
+ (if (and abbrev-mode
+ (eq (char-syntax (preceding-char)) ?w))
+ (expand-abbrev))
(let ((start-column (current-column))
indent)
(save-excursion
(or (= (point) end) (setq indent (current-column))))))
(if indent
(let ((opoint (point-marker)))
- (delete-region (point) (progn (skip-chars-backward " \t") (point)))
(indent-to indent 0)
(if (> opoint (point))
(goto-char opoint))
(move-marker opoint nil))
(tab-to-tab-stop))))
-(defvar tab-stop-list
+(defcustom tab-stop-list
'(8 16 24 32 40 48 56 64 72 80 88 96 104 112 120)
- "*List of tab stop positions used by `tab-to-tab-stops'.")
+ "*List of tab stop positions used by `tab-to-tab-stop'.
+This should be a list of integers, ordered from smallest to largest."
+ :group 'indent
+ :type '(repeat integer))
-(defvar edit-tab-stops-map nil "Keymap used in `edit-tab-stops'.")
-(if edit-tab-stops-map
- nil
- (setq edit-tab-stops-map (make-sparse-keymap))
- (define-key edit-tab-stops-map "\C-x\C-s" 'edit-tab-stops-note-changes)
- (define-key edit-tab-stops-map "\C-c\C-c" 'edit-tab-stops-note-changes))
+(defvar edit-tab-stops-map
+ (let ((map (make-sparse-keymap)))
+ (define-key map "\C-x\C-s" 'edit-tab-stops-note-changes)
+ (define-key map "\C-c\C-c" 'edit-tab-stops-note-changes)
+ map)
+ "Keymap used in `edit-tab-stops'.")
(defvar edit-tab-stops-buffer nil
"Buffer whose tab stops are being edited--in case
The variable `tab-stop-list' is a list of columns at which there are tab stops.
Use \\[edit-tab-stops] to edit them interactively."
(interactive)
- (if abbrev-mode (expand-abbrev))
+ (and abbrev-mode (= (char-syntax (preceding-char)) ?w)
+ (expand-abbrev))
(let ((tabs tab-stop-list))
(while (and tabs (>= (current-column) (car tabs)))
(setq tabs (cdr tabs)))
(if tabs
- (indent-to (car tabs))
+ (let ((opoint (point)))
+ (delete-horizontal-space t)
+ (indent-to (car tabs)))
(insert ?\ ))))
(defun move-to-tab-stop ()
(while (and tabs (>= (current-column) (car tabs)))
(setq tabs (cdr tabs)))
(if tabs
- (move-to-column (car tabs) t))))
+ (let ((before (point)))
+ (move-to-column (car tabs) t)
+ (save-excursion
+ (goto-char before)
+ ;; If we just added a tab, or moved over one,
+ ;; delete any superfluous spaces before the old point.
+ (if (and (eq (preceding-char) ?\ )
+ (eq (following-char) ?\t))
+ (let ((tabend (* (/ (current-column) tab-width) tab-width)))
+ (while (and (> (current-column) tabend)
+ (eq (preceding-char) ?\ ))
+ (forward-char -1))
+ (delete-region (point) before))))))))
(define-key global-map "\t" 'indent-for-tab-command)
-(define-key esc-map "\034" 'indent-region)
+(define-key esc-map "\C-\\" 'indent-region)
(define-key ctl-x-map "\t" 'indent-rigidly)
(define-key esc-map "i" 'tab-to-tab-stop)