Emacs Shift-Tab向左移动块

时间:2010-02-12 05:59:35

标签: emacs

如何让emacs转换为将所选文本向左移动4个空格?

4 个答案:

答案 0 :(得分:49)

为此,我使用绑定到indent-rigidly的命令C-x TAB。给它参数-4将选定区域向左移动四个空格:C-u -4 C-x TAB

http://www.gnu.org/s/emacs/manual/html_node/elisp/Region-Indent.html

答案 1 :(得分:12)

这将从当前行的前面删除4个空格(如果存在空格)。

(global-set-key (kbd "<S-tab>") 'un-indent-by-removing-4-spaces)
(defun un-indent-by-removing-4-spaces ()
  "remove 4 spaces from beginning of of line"
  (interactive)
  (save-excursion
    (save-match-data
      (beginning-of-line)
      ;; get rid of tabs at beginning of line
      (when (looking-at "^\\s-+")
        (untabify (match-beginning 0) (match-end 0)))
      (when (looking-at "^    ")
        (replace-match "")))))

如果你的变量tab-width碰巧是4(这就是你要“撤消”的那个),那么你可以用(looking-at "^ ")这样更通用的东西替换(concat "^" (make-string tab-width ?\ ))

此外,代码会使用untabify将行前面的标签转换为空格。

答案 2 :(得分:8)

我制作了一些功能,用于向左或向右四个空格标记区域,具体取决于您是使用制表符还是Shift +制表符:

(defun indent-region-custom(numSpaces)
    (progn 
        ; default to start and end of current line
        (setq regionStart (line-beginning-position))
        (setq regionEnd (line-end-position))

        ; if there's a selection, use that instead of the current line
        (when (use-region-p)
            (setq regionStart (region-beginning))
            (setq regionEnd (region-end))
        )

        (save-excursion ; restore the position afterwards            
            (goto-char regionStart) ; go to the start of region
            (setq start (line-beginning-position)) ; save the start of the line
            (goto-char regionEnd) ; go to the end of region
            (setq end (line-end-position)) ; save the end of the line

            (indent-rigidly start end numSpaces) ; indent between start and end
            (setq deactivate-mark nil) ; restore the selected region
        )
    )
)

(defun untab-region (N)
    (interactive "p")
    (indent-region-custom -4)
)

(defun tab-region (N)
    (interactive "p")
    (if (active-minibuffer-window)
        (minibuffer-complete)    ; tab is pressed in minibuffer window -> do completion
    ; else
    (if (string= (buffer-name) "*shell*")
        (comint-dynamic-complete) ; in a shell, use tab completion
    ; else
    (if (use-region-p)    ; tab is pressed is any other buffer -> execute with space insertion
        (indent-region-custom 4) ; region was selected, call indent-region
        (insert "    ") ; else insert four spaces as expected
    )))
)

(global-set-key (kbd "<backtab>") 'untab-region)
(global-set-key (kbd "<tab>") 'tab-region)

编辑:添加了Maven的代码以检查是否在迷你缓冲区中,以及特定缓冲区中的标签完成情况(例如 shell )。

答案 3 :(得分:1)

我对Stanley Bak的回答有所改进。 对我来说,这个全局密钥绑定搞乱了迷你缓冲区的完成。

所以我也为迷你缓冲区提供了一个案例。

修改:重命名indent-region - &gt; indent-region-custom

indent-region与现有命令发生冲突,并为save(保存前的hook)和其他一些组合键提供了缩进错误。

(defun indent-region-custom(numSpaces)
  (progn
    ;; default to start and end of current line
    (setq regionStart (line-beginning-position))
    (setq regionEnd (line-end-position))
    ;; if there's a selection, use that instead of the current line
    (when (use-region-p)
      (setq regionStart (region-beginning))
      (setq regionEnd (region-end))
      )

    (save-excursion ; restore the position afterwards
      (goto-char regionStart) ; go to the start of region
      (setq start (line-beginning-position)) ; save the start of the line
      (goto-char regionEnd) ; go to the end of region
      (setq end (line-end-position)) ; save the end of the line

      (indent-rigidly start end numSpaces) ; indent between start and end
      (setq deactivate-mark nil) ; restore the selected region
      )
    )
  )

(defun untab-region (N)
  (interactive "p")
  (indent-region-custom -4)
  )

(defun tab-region (N)
  (interactive "p")
  (if (active-minibuffer-window)
      (minibuffer-complete)    ; tab is pressed in minibuffer window -> do completion
    (if (use-region-p)    ; tab is pressed is any other buffer -> execute with space insertion
        (indent-region-custom 4) ; region was selected, call indent-region-custom
      (insert "    ") ; else insert four spaces as expected
      )
    )
  )

(global-set-key (kbd "<backtab>") 'untab-region)
(global-set-key (kbd "<tab>") 'tab-region)