Two code snippets that solved problems random people on
had. The first implements a specific behavior for
the other toggles case at point.
Kill Region or to Beginning of Line
One user was confused by the behavior of
(by default on
C-w), which deletes the current region and
appends it to the kill ring. Emacs traditionally differs from modern
systems by always having a region (the equivalent to a
Emacs monitors two special positions in any buffer. The first is
called “point.” It’s the place where you enter text. The second is
“mark,” and is some other place in the buffer. You can set mark using
C-SPC. The text between point and mark is called “the
region,” and many commands work on the region.
What confuses newer users not used to this is that you can not
usually see the region. To alleviate this and add some other
features, Emacs has for some time now added the so-called transient
mark mode, in which the region is highlighted until a non-region
moving command is issued. This implements most of the effects that newer
users expect. Except, well, when they use
C-w when no
region is selected, (apparently) random parts of text vanish.
The following code changes that behavior. When the region is “active,” i.e. highlighted, it is deleted and appended to the kill ring as usual. When it is not active, the command will delete the current line (from point to the beginning of the line) and append it to the kill ring.
Not something I would use, but it seems to have solved that user’s problem.
(defun weird-c-w-command () "Kill the region if active. Else, kill to beginning of line." (interactive) (if (region-active-p) (call-interactively 'kill-region) (kill-region (point-at-bol) (point))))
Add that and the following to your
.emacs to use it
instead of the default for
(global-set-key (kbd "C-w") 'weird-c-w-command)
Toggle Case at Point
Another user was used to vi’s command to toggle case at point. While
Emacsers usually would use
capitalize or lower-case the current word starting at the current
char, Emacs is customizeable to accomodate user’s wishes.
(defun toggle-case () "Toggle the case of the char at point." (interactive) (let ((char (buffer-substring (point) (1+ (point))))) (if (equal (upcase char) char) (downcase-region (point) (1+ (point))) (upcase-region (point) (1+ (point))))))
Bind to a key of your preference. Note that this is not exactly
equivalent to the vi command
~, but the differences can
be implemented if needed.