64
C-h b will list all the bindings available in a buffer. This is a mnemonic for help (C-h) bindings (b).
You can also get a list of keybindings via C-h m, which is help for the major and minor modes for the buffer. The formatting of this is a little clearer, but includes additional information about the modes beyond just listing the keybindings.
60
I think the simplest way is to check the value of the buffer-local major-mode variable, with either of:
C-hv major-mode RET
M-: major-mode RET
49
There is a "shortcut" approach too for the same solution if you don't want to define your own minor mode (that I talk about in my first answer).
You can install the use-package package available from Melpa and make use of bind-key* or bind-keys* macro that's part of the bind-key package that ships with use-package.
From the documentation of bind-key.el:
;;...
35
See the Stack Exchange for Emacs project. From their page:
SX will be a full featured Stack Exchange mode for GNU Emacs 24+.
Using the official API, we aim to create a more versatile experience
for the Stack Exchange network within Emacs itself.
34
You can define your own minor mode and its key map and have that override all other modes (minor + major). That's exactly why I chose to write my own minor mode.
Steps to have your key bindings override all bindings:
Defining your own minor mode and key map as shown below.
Activate your minor mode globally
(define-key my-mode-map (kbd "C-j") #'newline-and-...
28
I use the command helm-descbinds, which is available via melpa. I mapped it to C-h b because it is basically a drop-in replacement for describe-bindings. The benefit is that it is easier to navigate and search than the output of describe-bindings because you can easily search for keywords and the helm buffer will narrow to show all of the matches, and ...
28
The full syntax for specifying file extensions for gnuplot-mode is:
(add-to-list 'auto-mode-alist '("\\.g\\'" . gnuplot-mode))
The other point to verify is that you are using Bruce Ravel's recent (year 2012) implementation of gnuplot-mode. This is a separate MELPA package that requires gnuplot version 4.4 and higher.
Lastly avoid gnuplot-mode files that ...
25
It will be convenient to bind the below function to a key binding of your choice.
If you are currently working on a FILE buffer, calling the below function will toggle between FILE's major-mode specific *scratch* buffer called *scratch-MAJOR-MODE* and the FILE buffer.
Given the example in question, if I am working on a Perl script called myperl.pl, calling ...
23
Add these lines to your .emacs file:
(require 'yaml-mode)
(add-to-list 'auto-mode-alist '("\\.ya?ml\\'" . yaml-mode))
The auto-mode-alist is a variable which emacs consults whenever a new file is opened. You can add mappings between filename patterns and major-modes.
You can find out more about how Emacs determines which modes to load for a given buffer ...
22
buffer-face-set and buffer-face-mode in Emacs 23 or later is designed for exactly this. From the Emacs wiki:
;; Use variable width font faces in current buffer
(defun my-buffer-face-mode-variable ()
"Set font to a variable width (proportional) fonts in current buffer"
(interactive)
(setq buffer-face-mode-face '(:family "Symbola" :height 100 :...
21
Documentation
The API completion at point function can be found in the documentation of completion-at-point-functions
Each function on this hook is called in turns without any argument and
should return either nil to mean that it is not applicable at point,
or a function of no argument to perform completion (discouraged), or a
list of the form (...
19
These are indeed escape sequences which the terminal should interpret as orders to change the text color. Normally they shouldn't be used when the compiler is invoked from Emacs (the terminal type should be set to dumb, which should cause the compiler to refrain from using any escape sequence). There may be something wrong in your configuration that causes ...
19
In Emacs terminology, these are two different steps:
Associate files with the .ts extension with the major mode typescript-mode.
Run the function tss-setup-current-buffer when Typescript mode starts.
To choose which major mode to use for certain file names, add an entry to the variable auto-mode-alist. Put the following line in your init file:
(add-to-...
answered May 14 '15 at 13:47
Gilles 'SO- stop being evil'
19.3k4 gold badges49 silver badges85 bronze badges
19
Solution 1:
Step 1, Use https://github.com/felipeochoa/rjsx-mode
Step 2, Install Emacs 25+, see https://github.com/mooz/js2-mode/issues/291
Step 3, Patch rjsx-mode with below code
(defadvice js-jsx-indent-line (after js-jsx-indent-line-after-hack activate)
"Workaround sgml-mode and follow airbnb component style."
(save-excursion
(beginning-of-...
18
Doing again an M-x org-mode does not turn it off.
This convention is for minor-modes - Doing a M-x "minor-mode-name" again disables that minor mode. org-mode is a major mode. When you do this, emacs has no clue which major mode to go into. There must be a major mode always active.
So, rather than disable org-mode, you have to think in terms of which major ...
16
The second approach is preferable as it modifies the mode's keymap just once.
If you do it using the mode's hook then that will be called every time that mode is enabled in some buffer. Doing so again usually won't actually have an effect because the keys are just again bound to what they are already bound to. Major mode keymaps are "local" to the major ...
15
When you use M-x find-file-literally Emacs will not invoke a mode that is based on the file name. Instead, it uses fundamental-mode as the major mode.
From the command line you can use something like this:
emacs --eval '(find-file-literally "yourfile.ext")'
14
C-h m gives you help on the current mode, and it typically tells you the name of the command that turns the mode on.
For example, in Emacs-Lisp mode C-h m tells you that you are in Emacs-Lisp mode. The command that turns the mode on is just emacs-lisp-mode.
C-h m also provides a link to the library that defines the mode, and if you click on that link it ...
14
The following should work:
(use-package js2-mode
:mode (("\\.js\\'" . js2-mode)
("\\.jsx\\'" . js2-mode))
...
:ensure t)
14
In the upcoming release of Emacs 27, JSX support is now built into the default JavaScript mode for Emacs, js-mode. (Try it out! You can build from
source using the Emacs 27 release candidate, or e.g. install a snapshot from a PPA, or install a DMG for macOS.)
If the use of JSX is anticipated, then JSX support will be automatically enabled in JavaScript ...
13
There are a number of ways to identify the major mode for a file that don't rely on an extension, see Choosing File Modes in the manual.
Depending on the kinds of files you are dealing with, perhaps you could use the magic-mode-alist. Also note that auto-mode-alist is not limited to matching extensions: you can match any part of the file name or path.
If ...
12
The auto-mode-alist variable does what you need. Never bind anything to the major-mode variable.
The documentation explains how you can set major-modes per file extension and, most importantly, it explains how to treat multiple extensions.
Alist of filename patterns vs corresponding major mode functions. Each element looks like (REGEXP . FUNCTION) or (...
12
The problem is that it is not more robust.
Firstly, the major modes are precisely the ones responsible for deciding what's a comment or a string. If they were able to successfully define them for the purpose of font-locking, they should be able to do the same for other purposes.
Secondly, reading the syntax to determine the context that point is inside is ...
12
This turned out to be simpler then expected. As suggested in the comments here and on the question:
(with-eval-after-load 'erc
(require 'markdown-mode)
(require 'cl-lib)
(setq erc-mode-map
(make-composed-keymap (cl-copy-list erc-mode-map)
markdown-mode-map)))
This will create a keymap which is a copy of erc-mode-...
12
When you run a process inside Emacs, that process is "inferior" (i.e. a subprocess).
IELM M-x ielm is the builtin Inferior Emacs Lisp Mode. It's relatively featureless, but can definitely come in handy. (Esp. for learning Elisp)
SLIME, the Superior Lisp Interaction Mode for Emacs, is mostly a joke on the whole "inferior" process name. SLIME is used ...
12
The command you need is electric-indent-local-mode. You can use this to turn off electric-indent-mode in any buffer by calling it manually: M-x electric-indent-local-mode. This is a toggle, so calling it again in the same buffer turns it back on again.
To do this automatically from your init file, you need to set up a hook. First, define the hook:
(defun ...
11
At the cost of an extra top-level symbol binding, there's a very neat solution which avoids repeating the define-derived-mode form:
(defalias 'my-fancy-parent-mode
(if (fboundp 'prog-mode) 'prog-mode 'fundamental-mode))
(define-derived-mode my-fancy-mode my-fancy-parent-mode
...)
Works fine in any Emacs >= 23. I came up with this for haml-mode a ...
11
edit-server might be of some help. It lets you edit any text field inside Chrome with Emacs and then send the text back to the browser with minimum effort. Not exactly what you wanted, but its an improvement.
11
Inside your hook put this: (setq comment-start "% "). Also, this will explain why:
comment-region is an interactive compiled Lisp function.
(comment-region BEG END &optional ARG)
Comment or uncomment each line in the region. With just C-u prefix
arg, uncomment each line in region BEG .. END. Numeric prefix ARG
means use ARG comment ...
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