Here are some examples of doing certain commonly desired things with Lisp expressions:
load-path. You can then put Lisp libraries that are not included with Emacs in this directory, and load them with M-x load-library. See Lisp Libraries.
(add-to-list 'load-path "/path/to/lisp/libraries")
TAB in C mode just insert a tab if point is in the middle of a
(setq c-tab-always-indent nil)
Here we have a variable whose value is normally
t for “true”
and the alternative is
nil for “false”.
Make searches case sensitive by default (in all buffers that do not override this).
(setq-default case-fold-search nil)
This sets the default value, which is effective in all buffers that do
not have local values for the variable (see Locals). Setting
setq affects only the current
buffer’s local value, which is probably not what you want to do in an
Specify your own email address, if Emacs can’t figure it out correctly.
(setq user-mail-address "[email protected]")
Various Emacs packages, such as Message mode, consult
user-mail-address when they need to know your email address.
See Mail Headers.
Make Text mode the default mode for new buffers.
(setq-default major-mode 'text-mode)
text-mode is used because it is the command for
entering Text mode. The single-quote before it makes the symbol a
text-mode would be treated as a variable
(add-hook 'text-mode-hook 'auto-fill-mode)
Load the installed Lisp library named
foo (actually a file
foo.el in a standard Emacs directory).
When the argument to
load is a relative file name, not starting
/’ or ‘
load searches the directories in
load-path (see Lisp Libraries).
Load the compiled Lisp file
foo.elc from your home directory.
Here a full file name is used, so no searching is done.
Tell Emacs to find the definition for the function
by loading a Lisp library named
mypackage (i.e., a file
(autoload 'myfunction "mypackage" "Do what I say." t)
Here the string
"Do what I say." is the function’s
documentation string. You specify it in the
definition so it will be available for help commands even when the
package is not loaded. The last argument,
t, indicates that
this function is interactive; that is, it can be invoked interactively
by typing M-x myfunction RET or by binding it to a key.
If the function is not interactive, omit the
t or use
Rebind the key C-x l to run the function
(see Init Rebinding).
(global-set-key "\C-xl" 'make-symbolic-link)
(define-key global-map "\C-xl" 'make-symbolic-link)
Note once again the single-quote used to refer to the symbol
make-symbolic-link instead of its value as a variable.
(define-key lisp-mode-map "\C-xl" 'make-symbolic-link)
next-linein Fundamental mode so that they run
(substitute-key-definition 'next-line 'forward-line global-map)
Make C-x C-v undefined.
One reason to undefine a key is so that you can make it a prefix.
Simply defining C-x C-v
anything will make C-x C-v a
prefix, but C-x C-v must first be freed of its usual non-prefix
$’ have the syntax of punctuation in Text mode. Note the use of a character constant for ‘
(modify-syntax-entry ?\$ "." text-mode-syntax-table)
(put 'narrow-to-region 'disabled nil)
Adjusting the configuration to various platforms and Emacs versions.
Users typically want Emacs to behave the same on all systems, so the same init file is right for all platforms. However, sometimes it happens that a function you use for customizing Emacs is not available on some platforms or in older Emacs versions. To deal with that situation, put the customization inside a conditional that tests whether the function or facility is available, like this:
(if (fboundp 'blink-cursor-mode) (blink-cursor-mode 0)) (if (boundp 'coding-category-utf-8) (set-coding-priority '(coding-category-utf-8)))
You can also simply disregard the errors that occur if the function is not defined.
(ignore-errors (set-face-background 'region "grey75"))
setq on a variable which does not exist is generally
harmless, so those do not need a conditional.