自动删除空白的函数

snippet

#1

效果: 把函数绑定到回格键,一般情况下正常删除,检测到有多余空白的时候会自动删除空白。并且光标前后都会处理。

Lisp:

其他:

代码:

(defvar moon-hungry-delete-black-list '(org-mode text-mode fundamental-mode markdown-mode)
  "A list of major mode in where `moon-hungry-delete' should behave like normal delete.")

(defun moon-hungry-delete ()
  "Smart and clean delete.
If we are at the beginning of a line, backspace
deletes all whitespace before and after point
and moves point to the previous line."
  (interactive)
  (require 'cl-lib)
  (cl-labels ((normal-delete () (if (region-active-p)
                                    (delete-region (region-beginning) (region-end))
                                  (if (and (not (eql (point) (point-max)))
                                           (eql (alist-get (char-before) '((?{ . ?}) (?\[ . ?\])
                                                                           (?\( . ?\)) (?\" . ?\")
                                                                           (?\' . ?\') (?“ . ?”) (?‘ . ?’)))
                                                (char-after)))
                                      ;; if we are in the middle of a empty pair, i.e., "|" or (|)
                                      ;; delete both
                                      (progn (forward-char)
                                             (backward-delete-char 2))
                                    (call-interactively #'backward-delete-char-untabify)))))
    (if (or (region-active-p)
            (<= (car (syntax-ppss)) 0)
            (minibufferp (current-buffer)))
        ;; if we are at top-level
        ;; do normal delete
        (normal-delete)
      ;; if the point is not before the line but inside it, do normal delete
      ;; otherwise do hungry delete
      ;;
      ;; 1. we first delete all white spaces, then insert newline and indent properly
      ;; 2. but if there is only a closing delimiter, i.e., } or ),
      ;;    we don't insert new line.
      ;; 3. if we ends up in the same place before hungry delete,
      ;;    that means the user is trying to delete back to the previous line,
      ;;    then do that.
      (let* ((point (point)) ; staring point
             (bolt (save-excursion
                     ;; `beginning-of-line-text' seems to ignore comment for some reason,
                     (beginning-of-line)
                     (skip-chars-forward " \t")
                     (point)))
             ;; beginning of the region that we are to delete
             (beg (save-excursion (while (member (char-before) '(?\n ?\s ?\t))
                                    (backward-char))
                                  (point)))
             ;; end of that region
             (end (save-excursion (goto-char bolt)
                                  (while (member (char-after) '(?\n ?\s ?\t))
                                    (forward-char))
                                  (point))))
        (if (<= point bolt)
            ;; actually decide to delete stuff
            (progn
              (delete-region beg end)
              (unless (eql (char-after) ?\))
                (call-interactively #'newline))
              ;; so we did all this and ends up not changing anything
              ;; why? because the user doesn't want to delete excess white space and add newline
              ;; but to delete back to previous line! do that.
              (when (eql (point) end)
                (delete-region beg end)
                (insert ?\s)))
          ;; not at beginning of text, just do normal delete
          (normal-delete))))))

#2

主题不错,求主题


#3

感谢,从这个进化到 moon-hungry-delete

(global-set-key (kbd "C-<backspace>") (lambda ()
                                        (interactive)
                                        (kill-line 0)
                                        (indent-according-to-mode)))

#4

和hungry-delete与smart-hungry-delete的不同是?


#5

没太大区别,细节上有一些不同:一是大括号会另起一行,而不是删除到行尾;二是如一楼所说,前后都会清理;三是在top level只做普通删除。

smart-hungry-delete不了解。


#6

自用主题,写得比较随便。