Binding similar commands from different modes to the same key - emacs

I use emacs in multiple modes (ESS, Auctex, Slime, elisp, etc...) all using evil-mode key-bindings. Each of the interaction modes have similar functions for evaluating regions, lines or buffers that I have bound to shortcuts using spacebar as a prefix.
;; bind slime's eval and elisp eval to the key sequence "<SPC>e"
(evil-define-key 'normal lisp-mode-map (kbd "<SPC>e") 'slime-eval-last-expression)
(evil-define-key 'normal lisp-interaction-mode-map (kbd "<SPC>e") 'eval-last-sexp)
I would like to set a default key for a "type" of function, so that I don't need to have an entry like the above for every interaction mode I use and for every command. This would hopefully give a more readable .emacs init file and make it easier to change my key-bindings in the future.
I'm fairly sure that I could do this myself using a series of hooks, but I wonder if there is any existing or built-in support for this?
Thanks
tensorproduct

I don't know anything about Evil, so I'll give the normal Emacs solution:
(global-set-key [?\s ?e] #'my-eval-last-sexp)
(defvar my-eval-last-sexp-command #'undefined)
(defun my-eval-last-sexp ()
(interactive)
(call-interactively my-eval-last-sexp-command))
(add-hook 'emacs-lisp-mode-hook
(lambda () (set (make-local-variable 'my-eval-last-sexp-command) #'eval-last-sexp))
(add-hook 'lisp-mode-hook
(lambda () (set (make-local-variable 'my-eval-last-sexp-command) #'slime-eval-last-expression))
...
As you can see, there's only one mention of the key you want (in this case [?\s ?e]). But you don't save much on the amount of code you have to write. You might improve it by making my-eval-last-sexp a bit more complex (e.g. it could try to guess the command name from the major mode name), or by replacing the hook function with a global alist.
Hopefully, in some future Emacs, all such source-code modes that interact with some interpreter/compiler will share more of their code so that your problem will simply disappear.

Related

Keep getting mode name when switching buffers in Emacs

I have strange thing in my Emacs and I can't locate it, everytime I switch a buffer I get message with major mode name even when I call the function I get minibuffer-inactive-mode
The only global function (for all modes) in my .emacs file (I think) is this:
(add-hook 'after-change-major-mode-hook (lambda ()
(if (not (memql (intern (major-mode))
'(fundamental-mode
erc-mode
text-mode
sql-mode)))
(local-set-key (kbd "RET")
'new-line-and-indent-fix))))
How to find the place that add this annoying thing? What different hook can be executed on each mode?
There is no major-mode function in vanilla Emacs. Whatever that function is in your config, it's probably responsible for displaying the message you're seeing.
You want to fix your code (as per Stefan's comment), but you probably also want to look into that non-standard function:
M-x find-function RET major-mode RET

Set custom keybinding for specific Emacs mode

Though I know how to set a global key-binding in Emacs, I find it hard to even Google out the code for a local (minor-mode specific) key-binding. For instance, I have this code in my .emacs:
;; PDFLaTeX from AucTeX
(global-set-key (kbd "C-c M-p")
(lambda ()
(interactive)
(shell-command (concat "pdflatex " buffer-file-name))))
I don't want to set it globally. Is there a function like local-set-key?
I use the following:
(add-hook 'LaTeX-mode-hook
(lambda () (local-set-key (kbd "C-0") #'run-latexmk)))
to have a bind defined for LaTeX mode alone.
To bind a key in a mode, you need to wait for the mode to be loaded before defining the key. One could require the mode, or use eval-after-load
(eval-after-load 'latex
'(define-key LaTeX-mode-map [(tab)] 'outline-cycle))
Don't forget either '—eval-after-load is not a macro, so it needs them.
You need to identify the key map for that mode (for example, LaTeX-mode-map) and use the function define-key. As an example, along with activating outline-minor-mode within LaTeX mode, I have:
(define-key LaTeX-mode-map [(tab)] 'outline-cycle))
In this case the major mode (LaTeX) holds the key binding, but there is also an outline-minor-mode-map.
None of the other answers satisfied my needs. So this may help other people. I wanted Tab to jump to the beginning of the line if I'm in Evil's normal mode (basically this means everywhere in Emacs), but I instead wanted it to cycle between org item states if I am in an org-mode document.
One option was to mess around with separate bindings and constant binding-rebinding whenever I switched buffers (because evil allows only one binding per key in its normal state).
But a more efficient option was to make Tab run my own code which runs the required function based on which major mode the current buffer uses. So if I am in a org buffer, this code runs org-cycle, and otherwise it runs evil-first-non-blank (go to the first non-whitespace character on the line).
The technique I used here can also be used by calling your custom function via global-set-key instead, for people who use regular non-evil Emacs.
For those who don't know Emacs lisp, the first line after the "if" statement is the true-action, and the line after that is the false-action. So if major-mode equals org-mode, we run org-cycle, otherwise we run evil-first-non-blank in all other modes:
(defun my/tab-jump-or-org-cycle ()
"jumps to beginning of line in all modes except org mode, where it cycles"
(interactive)
(if (equal major-mode 'org-mode)
(org-cycle)
(evil-first-non-blank))
)
(define-key evil-normal-state-map (kbd "<tab>") 'my/tab-jump-or-org-cycle)

How to minify .emacs configuration file?

I was wondering if anyone can provide me with some help on minifying my .emacs file.
Currently I have it set up where each language I use have a custom tab, for example, if I have a hook for Java, it would look like this.
;; Java Hook
(defun e-java-mode-hook ()
(setq tab-width 4)
(setq indent-tabs-mode t)
(define-key java-mode-map (kbd "") 'java-insert-tab))
(defun java-insert-tab (&optional arg)
(interactive "P")
(insert-tab arg))
(add-hook 'java-mode-hook 'e-java-mode-hook)
And if I were to add another language like CSS or JavaScript, I would add another hook for CSS and another hook for JavaScript. So I was wondering if there's a global way of setting it so it would apply to any and all language?
I am currently running GNU Emacs 23.2.1 on Windows 7.
I agree with Tyler; although it's a bit complicated, you would be better off in the long run if you try to understand and customize the default indentation features. The Emacs Wiki has good resources, and there are other relevant Q&As here on Stack Overflow.
Binding the tab key to insert-tab means you completely lose the benefit of the likes of indent-region, and any other intelligent behaviour that a major mode might offer.
To address your specific questions regardless, however:
1) If you are defining (java-insert-tab) and (css-insert-tab) and (javascript-insert-tab) etc, and they all do exactly the same thing... well, hopefully you can see that you don't actually need more than one of those functions. Just give it a more generic name, and re-use it.
2) (local-set-key ...) does the same thing as (define-key (current-local-map) ...), which means you can also have a single generic function to override the tab keybinding, regardless of the major mode.
(defun my-coding-config ()
(setq tab-width 4)
(setq indent-tabs-mode t)
(local-set-key (kbd "<tab>") 'my-insert-tab))
(defun my-insert-tab (&optional arg)
(interactive "P")
(insert-tab arg))
Then you just need to add my-coding-config to each applicable mode hook variable. If there are a lot of them, you might wrap it up in a list like this:
;; Use my coding hook for all programming modes
(mapcar
(lambda (language-mode-hook)
(add-hook language-mode-hook 'my-coding-config))
'(java-mode-hook
javascript-mode-hook
css-mode-hook
...))
3) If you look at C-h v tab-width RET and likewise for indent-tabs-mode, you'll notice that they both say "Automatically becomes buffer-local when set in any fashion."
As an alternative to the customize interface already mentioned, you can use (set-default 'indent-tabs-mode t) to establish the default value for such variables. In the absence of code which sets a buffer-local value, all of your buffers will use the default, which might help you to avoid writing unnecessary mode hooks.
I'm not sure what you're trying to do. If you want to set the tab-width to 4 spaces globally, then you can do that using the customize command:
M-x customize-variable tab-width <ret>
Any changes you make to tab-width in customize will be applied globally. So you won't need to set it individually for each mode with hooks.
If you have different settings you want to apply to different modes, you will necessarily have to have code specific for each mode in your .emacs.
More generally, it looks like you're trying to build your own custom tab insertion commands - does the built-in indentation not do what you need? I think it will be easier to customize the indentation settings in Emacs than to manually insert tabs where you want them.
If you haven't already, take a look at the manual section on indentation and see if you might be able to do what you need without a lot of extra hooks:
C-h r m Indentation
(that is: h-elp, r-ead the manual, m-enu item Indentation)
or:
(info "(emacs)Indentation")
espect.el is doing exactly what you want.
From the docs:
This mode makes it easy to configure settings for individual
buffers with a concice and extensible mini-language. It abstracts
away common configuration selection tasks, like checking the mode
or filename, into a simple declarative syntax. Declare conditions;
run a function when the new buffer matches them. This makes it
easy to do things like turn on flyspell-prog-mode for your favorite
programming languages, or make all text-mode buffers ending in .mkn
have special properties.

Globally override key binding in Emacs

How can I set a key binding that globally overrides and takes precedence over all other bindings for that key? I want to override all major/minor mode maps and make sure my binding is always in effect.
This of course doesn't work:
(global-set-key "\C-i" 'some-function)
It works in text-mode, but when I use lisp-mode, C-i is rebound to lisp-indent-line.
I can go through and override this binding in lisp-mode and in every other mode individually, but there must be an easier way. Every time I install a new mode for a new file type, I'd have to go back and check to make sure that all of my key bindings aren't being overridden by the new mode.
I want to do this because I want to emulate bindings I've already learned and ingrained from other editors.
I use a minor mode for all my "override" key bindings:
(defvar my-keys-minor-mode-map
(let ((map (make-sparse-keymap)))
(define-key map (kbd "C-i") 'some-function)
map)
"my-keys-minor-mode keymap.")
(define-minor-mode my-keys-minor-mode
"A minor mode so that my key settings override annoying major modes."
:init-value t
:lighter " my-keys")
(my-keys-minor-mode 1)
This has the added benefit of being able to turn off all my modifications in one fell swoop (just disable the minor mode) in case someone else is driving the keyboard or if I need to see what a default key binding does.
Note that you may need to turn this off in the minibuffer:
(defun my-minibuffer-setup-hook ()
(my-keys-minor-mode 0))
(add-hook 'minibuffer-setup-hook 'my-minibuffer-setup-hook)
As an addition to scottfrazer's answer, I've written the following so that my keybindings retain precedence, even if subsequently-loaded libraries bring in new keymaps of their own.
Because keymaps can be generated at compile time, load seemed like the best place to do this.
(add-hook 'after-load-functions 'my-keys-have-priority)
(defun my-keys-have-priority (_file)
"Try to ensure that my keybindings retain priority over other minor modes.
Called via the `after-load-functions' special hook."
(unless (eq (caar minor-mode-map-alist) 'my-keys-minor-mode)
(let ((mykeys (assq 'my-keys-minor-mode minor-mode-map-alist)))
(assq-delete-all 'my-keys-minor-mode minor-mode-map-alist)
(add-to-list 'minor-mode-map-alist mykeys))))
Install use-package, eval and you're done:
(require 'bind-key)
(bind-key* "C-i" 'some-function)
I found this question while searching for "emacs undefine org mode keybindings", because I wanted to unbind the existing C-c C-b behavior to allow my global map to bury-buffer to work in an org buffer.
This ended up being the simplest solution for me:
(add-hook 'org-mode-hook
(lambda ()
(local-unset-key (kbd "C-c C-b"))))
Although scottfrazer's answer is exactly what you asked for, I will mention for posterity another solution.
From The Emacs Manual:
"Don't define C-c letter as a key in Lisp programs. Sequences consisting of C-c and a letter (either upper or lower case) are reserved for users; they are the only sequences reserved for users, so do not block them."
If you bind your personal global bindings to C-c plus a letter, then you "should" be safe. However, this is merely a convention, and any mode is still able to override your bindings.
If you want to "always use the keybinds in the map, unless I explicitly override them for a specific mode-map", and assuming you are using scottfrazier's approach, you want:
(defun locally-override (key cmd)
(unless (local-variable-p 'my-keys-minor-mode-map)
(set (make-variable-buffer-local 'my-keys-minor-mode-map)
(make-sparse-keymap))
(set-keymap-parent my-keys-minor-mode-map
(default-value 'my-keys-minor-mode-map)))
(define-key my-keys-minor-mode-map key cmd))
So
(locally-override "\C-i" nil)
should remove the "\C-i" binding from the minor mode in the current buffer only. Warning: this is completely untested, but seems like the right approach. The point of setting the parent rather than just coping the global value of my-keys-minor-mode-map is so any later changes to the global value are automatically reflected in the local value.
I don't think you can. That is roughly equivalent to saying that you want to define a global variable that cannot be hidden by local variable declarations in functions. Scope just doesn't work that way.
However, there might be a way to write an elisp function to go through the mode list and reassign it in every single one for you.
Unless you really want to do this yourself, you should check around and see if anyone else already has done it.
There is a package for Emacs which gives your windows-like keybindings. You should be able to find it through google.

How to accomplish equivalent of Vim's Ctrl-n in GNU Emacs?

Vim's Ctrl+N generally works like this: I type few letters, hit Ctrl+N, and Vim provides me with completions based on words in my all opened buffers.
Solution for Emacs doesn't have to be identical. I mainly use it like this: declare variable, then use it in later code. But I like the lightweight approach of not parsing the source code.
You want dabbrev-expand, bound to M-/ by default. I haven't used Vim, but from your description, it does the exact same thing.
try hippie-expand, bound to your favorite key
(global-set-key (kbd "M-/") 'hippie-expand)
Instead of presenting a completion-list, repeatedly hitting the bound-key cycles through the completions in-place.
Why "hippie"-expand? I have no idea, and I actually avoided looking at the function because the name was uninformative and off-putting, until I read the write-up at 'Life Is Too Short For Bad Code'. (The EmacsWiki entry on hippie-expand also asks "why 'hippie?'" but can't answer it, either.)
I personally use AutoComplete It gives you a nice dropdown box. You can select how many letters you want to type before it activates and customise what you want to show up, including stuff in dabbrev-expand.
;; Allow tab to autocomplete
(defun indent-or-expand (arg)
"Either indent according to mode, or expand the word preceding point."
(interactive "*P")
(if (and
(or (bobp) (= ?w (char-syntax (char-before))))
(or (eobp) (not (= ?w (char-syntax (char-after))))))
(dabbrev-expand arg)
(tab-to-tab-stop)))
(defun my-tab-fix ()
(local-set-key [tab] 'indent-or-expand))
(add-hook 'as-mode-hook 'my-tab-fix)
(add-hook 'java-mode-hook 'my-tab-fix)
(add-hook 'c-mode-hook 'my-tab-fix)
(add-hook 'sh-mode-hook 'my-tab-fix)
(add-hook 'emacs-lisp-mode-hook 'my-tab-fix)
The matter, in my opinion is that emacs completion I tryed doesn't complete regarding the context.
For instance, if you write some OOP with a method foobar() and an argument foo, M-/ will suggest you both foo and foobar.
But it would be great if you are calling an object method, not to provide just "foo" completion.
Has anyone a solution?
Aif> This requires much more than what "hippie expand" has to offer. If you code C/C++ you COULD use ECB http://ecb.sourceforge.net/ but frankly, the project is quite dead and this addon is not very reliable. If you need really good intelligent completion you should try Eclipse (CDT). But if you code python then Emacs (rope + flymake) is just as fine as Eclipse (PyDev).