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(emacs-lisp-intro.info)Keybindings

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Some Keybindings
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   Now for some personal keybindings:

     ;;; Compare windows
     (global-set-key "\C-cw" 'compare-windows)

   `compare-windows' is a nifty command that compares the text in your
current window with text in the next window.  It makes the comparison
by starting at point in each window, moving over text in each window as
far as they match.  I use this command all the time.

   This also shows how to set a key globally, for all modes.

   The command is `global-set-key'.  It is followed by the keybinding.
In a `.emacs' file, the keybinding is written as shown: `\C-c' stands
for `control-c', which means `press the control key and the `c' key at
the same time'.  The `w' means `press the `w' key'.  The keybinding is
surrounded by double quotation marks.  In documentation, you would
write this as `C-c w'.  (If you were binding a <META> key, such as
`M-c', rather than a <CTL> key, you would write `\M-c'.  Note:
Rebinding Keys in Your Init File, for details.)

   The command invoked by the keys is `compare-windows'.  Note that
`compare-windows' is preceded by a single quote; otherwise, Emacs would
first try to evaluate the symbol to determine its value.

   These three things, the double quotation marks, the backslash before
the `C', and the single quote mark are necessary parts of keybinding
that I tend to forget.  Fortunately, I have come to remember that I
should look at my existing `.emacs' file, and adapt what is there.

   As for the keybinding itself: `C-c w'.  This combines the prefix
key, `C-c', with a single character, in this case, `w'.  This set of
keys, `C-c' followed by a single character, is strictly reserved for
individuals' own use.  (I call these `own' keys, since these are for my
own use.)  You should always be able to create such a keybinding for
your own use without stomping on someone else's keybinding.  If you
ever write an extension to Emacs, please avoid taking any of these keys
for public use.  Create a key like `C-c C-w' instead.  Otherwise, we
will run out of `own' keys.

   Here is another keybinding, with a comment:

     ;;; Keybinding for `occur'
     ; I use occur a lot, so let's bind it to a key:
     (global-set-key "\C-co" 'occur)

   The `occur' command shows all the lines in the current buffer that
contain a match for a regular expression.  Matching lines are shown in
a buffer called `*Occur*'.  That buffer serves as a menu to jump to
occurrences.

   Here is how to unbind a key, so it does not work:

     ;;; Unbind `C-x f'
     (global-unset-key "\C-xf")

   There is a reason for this unbinding: I found I inadvertently typed
`C-x f' when I meant to type `C-x C-f'.  Rather than find a file, as I
intended, I accidentally set the width for filled text, almost always
to a width I did not want.  Since I hardly ever reset my default width,
I simply unbound the key.

   The following rebinds an existing key:

     ;;; Rebind `C-x C-b' for `buffer-menu'
     (global-set-key "\C-x\C-b" 'buffer-menu)

   By default, `C-x C-b' runs the `list-buffers' command.  This command
lists your buffers in _another_ window.  Since I almost always want to
do something in that window, I prefer the  `buffer-menu' command, which
not only lists the buffers, but moves point into that window.