ambevar-dotfiles/.emacs.d/functions.el

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;; FUNCTIONS
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;;==============================================================================
;; Unfill paragraph
;;==============================================================================

(defun unfill-paragraph ()
  (interactive)
  (let ((fill-column (point-max)))
    (fill-paragraph nil)))

(defun unfill-region ()
  (interactive)
  (let ((fill-column (point-max)))
    (fill-region (region-beginning) (region-end) nil)))


;; Remove duplicate lines. (sort -u)
(defun remove-dup ()
  (interactive)
  (shell-command-on-region (point) (mark) "sort -u" (buffer-name) t)
)

(defun dtwi () "Delete trailing whitespaces interactively."
  (interactive)
  (query-replace-regexp " +
" "
"))

;;==============================================================================
;; Toggle window split
;;==============================================================================
(defun my-toggle-window-split ()
  "Vertical split shows more of each line, horizontal split shows
more lines. This code toggles between them. It only works for
frames with exactly two windows."
  (interactive)
  (if (= (count-windows) 2)
      (let* ((this-win-buffer (window-buffer))
             (next-win-buffer (window-buffer (next-window)))
             (this-win-edges (window-edges (selected-window)))
             (next-win-edges (window-edges (next-window)))
             (this-win-2nd (not (and (<= (car this-win-edges)
                                         (car next-win-edges))
                                     (<= (cadr this-win-edges)
                                         (cadr next-win-edges)))))
             (splitter
              (if (= (car this-win-edges)
                     (car (window-edges (next-window))))
                  'split-window-horizontally
                'split-window-vertically)))
        (delete-other-windows)
        (let ((first-win (selected-window)))
          (funcall splitter)
          (if this-win-2nd (other-window 1))
          (set-window-buffer (selected-window) this-win-buffer)
          (set-window-buffer (next-window) next-win-buffer)
          (select-window first-win)
          (if this-win-2nd (other-window 1))))))

(define-key my-keys-minor-mode-map [(control c) (|)] 'my-toggle-window-split)

;;==============================================================================
;; Duplicate line
;;==============================================================================
(defun duplicate-line (arg)
  "Duplicate current line, leaving point in lower line."
  (interactive "*p")

  ;; save the point for undo
  (setq buffer-undo-list (cons (point) buffer-undo-list))

  ;; local variables for start and end of line
  (let ((bol (save-excursion (beginning-of-line) (point)))
        eol)
    (save-excursion

      ;; don't use forward-line for this, because you would have
      ;; to check whether you are at the end of the buffer
      (end-of-line)
      (setq eol (point))

      ;; store the line and disable the recording of undo information
      (let ((line (buffer-substring bol eol))
            (buffer-undo-list t)
            (count arg))
        ;; insert the line arg times
        (while (> count 0)
          (newline)         ;; because there is no newline in 'line'
          (insert line)
          (setq count (1- count)))
        )

      ;; create the undo information
      (setq buffer-undo-list (cons (cons eol (point)) buffer-undo-list)))
    ) ; end-of-let

  ;; put the point in the lowest line and return
  (next-line arg))

;; Binding.
(define-key my-keys-minor-mode-map (kbd "C-c C-d") 'duplicate-line)

;;==============================================================================
;; Comment DWIM -- toggle comment line
;;==============================================================================

;; Original idea from
;; http://www.opensubscriber.com/message/emacs-devel@gnu.org/10971693.html
(defun comment-dwim-line (&optional arg)
  "Replacement for the comment-dwim command. If no region is
selected and current line is not blank and we are not at the end
of the line, then comment current line.  Replaces default
behaviour of comment-dwim, when it inserts comment at the end of
the line."
  (interactive "*P")
  (comment-normalize-vars)
  ;; (if (and (not (region-active-p)) (not (looking-at "[ \t]*$")))
  (if (and (not (region-active-p)) )
      (comment-or-uncomment-region (line-beginning-position) (line-end-position))
    (comment-dwim arg)))

;; Binding.
(define-key my-keys-minor-mode-map "\M-;" 'comment-dwim-line)

;;==============================================================================
;; Window resize
;;==============================================================================
;; Only works for 2 vertical side-by-side.

(defun xor (b1 b2)
  "Exclusive or of its two arguments."
  (or (and b1 b2)
      (and (not b1) (not b2))))

(defun move-border-left-or-right (arg dir)
  "General function covering move-border-left and move-border-right. If DIR is
     t, then move left, otherwise move right."
  (interactive)
  (if (null arg) (setq arg 5))
  (let ((left-edge (nth 0 (window-edges))))
    (if (xor (= left-edge 0) dir)
        (shrink-window arg t)
      (enlarge-window arg t))))

(defun move-border-left (arg)
  "If this is a window with its right edge being the edge of the screen, enlarge
     the window horizontally. If this is a window with its left edge being the edge
     of the screen, shrink the window horizontally. Otherwise, default to enlarging
     horizontally.

     Enlarge/Shrink by ARG columns, or 5 if arg is nil."
  (interactive "P")
  (if (= (count-windows) 2)
      (move-border-left-or-right arg t)))

(defun move-border-right (arg)
  "If this is a window with its right edge being the edge of the screen, shrink
     the window horizontally. If this is a window with its left edge being the edge
     of the screen, enlarge the window horizontally. Otherwise, default to shrinking
     horizontally.

     Enlarge/Shrink by ARG columns, or 5 if arg is nil."
  (interactive "P")
  (if (= (count-windows) 2)
      (move-border-left-or-right arg nil)))

(define-key my-keys-minor-mode-map (kbd "M-(") 'move-border-left)
(define-key my-keys-minor-mode-map (kbd "M-)") 'move-border-right)

;;==============================================================================
;; Elisp eval
;;==============================================================================
(defun eval-and-replace ()
  "Replace the preceding sexp with its value."
  (interactive)
  (backward-kill-sexp)
  (condition-case nil
      (prin1 (eval (read (current-kill 0)))
             (current-buffer))
    (error (message "Invalid expression")
           (insert (current-kill 0)))))