How to restored default keymap without restarting Emacs? - emacs

I've somehow corrupted the key bindings in my current Emacs session.
Specifically, typing shift-M produces "m", rather than "M". This problem affects only the M key1.
My question is: how can I restore the default key bindings without restarting Emacs?
1I'm confident that the problem is a corrupted Emacs keymap. Typing the same shift-M key combination in other applications, or in other Emacs sessions (but, of course, still using the same keyboard, computer, etc.) produces the correct "M". Incidentally typing m (without shift-) in the Emacs session with the corrupted keymap works fine; it produces "m", as expected.

What does C-h k Shift-m say? If it got rebound, that call will tell you what it is bound to. It should be bound to self-insert-command.
Something like (global-set-key (kbd "M") 'self-insert-command) should do the trick to set it back. You can execute that using ielm or M-:. You might need to cut and paste the capital M from another app to type that, though.

Related

can't remap C-v in emacs

I want to remap Control-v for it to use my custom function, but it looks like I can't do that. I'm running emacs in terminal.
(global-unset-key "\C-v")
(global-set-key "\C-v" 'my-cut-or-paste)
If I try to unset first, C-h k just not showing any binding for this shortcut, and C-v just do nothing. If not unsetting shortcut, its not get remapped... The strange thing is how C-h k showing different keys for such shortcuts. For example - one time it can show
r runs the command self-insert-command, which is an interactive
other time (after emacs reload)
i runs the command self-insert-command, which is an interactive
If I try to set my function to such keys (i or r), C-v gets remapped, but those keys (i or r) are mapped to my function too, so I cant type.
Is this kind of 'terminal-related' key sequences? Is it able to do at all? thx.
My guess would be that your terminal is intercepting C-v as a paste-from-clipboard command.
If your clipboard has something that starts with i, you see:
i runs the command self-insert-command, which is an interactive
Similar for "r" or other letters. Emacs is blind to the fact that the "letters" come from a external paste, not from your keyboard. You should check the configuration options of your terminal, to see if you can unset that key.

Key bindings do not work in emacs scheme mode

I am following the guide here for emacs lisp interface.
C-c q is supposed to quit scheme mode. However this shows C-c q is undefined error. Typing (exit) on REPL works fine. Why is this key not bound in my emacs?
I see "Note that in any given implementation, only a subset of the following keys is available", but more importantly I don't believe that documentation is talking about Emacs bindings.
My impression is that those are the bindings recognised by the REPL if you were to run it outside of Emacs.
Inside Emacs you possibly need a prefix to say "send the next sequence to the REPL". e.g. in Emacs' term you have to type C-c C-c instead of just C-c to send an interrupt to the terminal. However as it's not listed in the other page which listed interrupts in Emacs, I suspect there actually isn't an equivalent binding. Or at least not by default.

Finding all the functions in various modes assigned to a specific shortcut

I'd like to find all the modes which do assign a function to some specific shortcut.
For example if I'm not mistaken a stock Emacs simply assigns (or defaults to) newline for S-return but while in org-mode S-return does invoke org-table-copy-down.
Is there an easy way to figure out which modes (both major and minor) do map a function to a specific shortcut? I can find all the shortcuts of one major mode using describe-mode but I'd like to find those for all the various modes. I don't mind if it were to only work for all the currently loaded modes.
Basically I'd like to find "free" or "relatively rarely re-mapped" key shortcuts, which are also easy to type (i.e. I'm not after doing "C-c a" because for a start C-c is a very convoluted key to reach and then having to then hit another key is one key too many for me. I'm more after re-mapping C-o, S-return, M-/ and other combo trivial and fast to reach).
You can find the current-mode bindings using C-h b.
You can get all of the keymaps currently available, using accessible-keymaps. You can find all the features loaded via variable features. But you would have to work to find all possible bindings for all possible modes from all files that you have loaded so far.
I recommend that you do it for a particular mode, one mode at a time. It's easy to check a given mode's key bindings.
You can even check the bindings of keymaps (such as minibuffer maps or the Isearch map) that are hard to see otherwise, if you use command C-h M-k (describe-keymap) from library `help-fns+.el. I use that when I want to see what keys are still available in a given keymap etc.
You can use
M-x describe-unbound-keys
to find out the free keys.
This is from third party library as said in comments.
I don't know the answer to your specific question, but I can give you my solution to getting easy-to-type keybindings that don't conflict with other modes.
In my set up, I've remappped CAPS-LOCK to Alt. Most people map it to CTRL, but I can hit CTRL relatively easily, while ALT is difficult. With this set-up, one of the easiest key combos to hit is M-space. So I use this as my own private keymap:
(define-prefix-command 'ty-keymap)
(global-set-key "\M- " ty-keymap)
(define-key ty-keymap " " 'just-one-space)
(define-key ty-keymap "j" 'join-next-line)
(define-key ty-keymap "s" 'mark-sexp)
(define-key ty-keymap "c" 'org-capture)
...
Note: by default, M-space is bound to just-one-space, which is useful. I've moved that to M-space-space. Bouncing my thumb twice on the spacebar is only a fraction slower than hitting it once, so it's not a big loss.
Since M-space isn't a keymap by default, this setup allows me to use all the keys on the keyboard, without further modification. That's a lot of real-estate, guaranteed to be free of any conflict with other packages - since well-behaved packages won't clobber a basic Emacs keybinding.
You might prefer another key combo, but the idea is the same. You could even use a function key as your prefix-command, so you could do <f5> followed by a letter for your commands.

Emacs define-key, Viper-mode key binding

I'm trying to learn emacs, getting vi custom key bindings.
Using Viper-mode, what is the correct way to re-bind a key? (I'm using Colemak keyboard layout(instead of qwerty) so have to change things like n->j) But would like it to work in viper-mode.
From this key binding guide on GNU.org:
http://www.gnu.org/software/emacs/manual/html_node/viper/Key-Bindings.html
It says the command to put in your .viper file is:
(define-key viper-vi-global-user-map "\C-v" 'scroll-down)
It doesn't work for me... in fact not sure I even have the function "define-key"...
M-x define-key [No match]
I'm not sure if 'define-key' is available on my version of emacs?
This works, but not in viper-mode
(global-set-key "n" "j")
Any help would be much appreciated. This is my first day using Emacs, to it's a pain getting Colemak & Viper-mode to work properly.
Thank for any help...
Hopefully some useful answers here:
First, having that line in the .viper works for me. Note that the viper-vi-global-user-map applies when you're in command mode, not insert mode.
Secondly, define-key isn't a command, it's a regular function, which just means that it cannot be called using M-x. See this Emacs wiki page for a little more detail on that distinction. But that was a good attempt.
Third, the global-set-key is a command, you could have tried making a change using M-x global-set-key. But, that sets the key in the current global map, which isn't the same as viper-vi-global-user-map. Viper-mode uses a bunch of different keymaps to make Emacs behave like vi, but all of the maps are overlaid on top of the global map.
I'm guessing that you found that C-v wasn't bound like you want when you're in insert mode. And that can be solved by adding this to your .viper:
(define-key viper-insert-global-user-map "\C-v" 'scroll-down)
Lastly, scroll-down may not be what you want. The down refers to the text moving down (given the perspective of a fixed window). C-v is generally bound to 'scroll-up. But,maybe it is exactly what you want.
Caveat: I'm not a viper-mode user, I don't even know how to use vi. So my terminology may be off. But I find the challenge of changing things in viper-mode very interesting.
Edited to add
From your comment it sounds like you want n to be the same as what j is bound to by default. Try adding this:
(define-key viper-vi-global-user-map "n" 'viper-next-line)
In "normal" mode I did M-x describe-key j, which told me that j is bound to 'viper-next-line, and the above line will bind n to the same routine. Repeat for the rest of the bindings you want to shift around.
in modern times evil-mode is the vim emulation layer for emacs, and to tweak it for colemak, my https://github.com/wbolster/evil-colemak-basics package helps a lot.

writing lisp emacs key binding and cannot specify the <delete> character

For some reason I got the default M-del key binding for backward-kill-word mapped to a scan for matching brackets and resetting is not working, so I am trying to set the global key binding in lisp. So I wrote in ~/.emacs.d/init.el the lisp commands:
(global-set-key (kbd "M-h") 'backward-kill-word)
(global-set-key (kbd "M-<\delete>") ‘backward-kill-word)
I tried them with C-x C-e and they both give the 'backward-kill-word output but only the first key-binding works "M-h", the other is ignored and M-del still trying the strange scanning action. The delete key works in emacs elsewhere, so it seems like "delete" is not being mapped to the physical key in lisp (and the backslash is there to show in this text only as the word was being commented out). Any idea what keyword to use or special character?
Best.
(I looked for libraries that may have overrided this command but I cannot find them)
On some systems, the delete key is defined as an alias to C-d. This is done through function-key-map on GNU Emacs <23 and local-function-key-map on GNU Emacs 23. (I've observed this behavior on Debian and Ubuntu 10.04 under X.) The purpose of such translations is to isolate people who code modes from the terminal intricacies: a mode that wants to shadow the delete command only needs to rebind C-d and not wonder if it should rebind delete (is that a delete left or delete right?) or deletechar or something else.
If there is a global or local binding for delete, it shadows this translation to C-d. However, if you press ESC delete, if there is no global or local binding for ESC delete, the second key is translated to C-d. This translation has precedence over the interpretation of ESC delete as M-delete. So ESC delete becomes equivalent to C-M-d.
This is arguably a bug in Emacs: the effect of ESC delete should be the same as M-delete, and there is no reason why ESC delete would run down-list which has nothing to do with deletion.
There are several possible fixes; I don't know which is best. One that should work with any version of Emacs is
(global-set-key [?\e delete] 'backward-kill-word)
The really nice thing about kbd is that what you type there is the same string that Emacs displays. So, try the following
C-h k M-<\delete> (to use your syntax)
or
M-x describe-key M-<\delete>
Emacs (for me) responds with:
M-DEL (translated from <M-delete>)
runs the command backward-kill-word,
which is an interactive compiled Lisp
function in `simple.el'.
It is bound to , M-DEL.
(backward-kill-word arg)
....
Which you can see shows that the representation for the key you want is M-DEL or M-delete.
Which is a long way of getting to the point that what you want is
(global-set-key (kbd "M-delete") 'backward-kill-word)
Of course, if you have something in your .emacs that overrides it, the above won't help. You'll need to find that included library and stop using it (or customize its behavior).
You might want to call global-set-key interactively to see how it interprets meta-delete. Also try local-set-key to ensure the strange binding is not mode-specific.
After not being able to find the library holding the conflict I found this webpage
http://www.cs.cmu.edu/cgi-bin/info2www?%28emacs%29Rebinding
Changing Key Bindings Interactively...
`M-x global-set-key KEY CMD '
Define KEY globally to run CMD....
Normally, C-z' is bound to the function
suspend-emacs' (when not using the X Window System), but you can
change C-z' to invoke an interactive subshell within Emacs, by binding
it toshell' as follows:
M-x global-set-key <RET> C-z shell <RET>
`global-set-key' reads the command name after the key. After you
press the key, a message like this appears so that you can confirm that
you are binding the key you want:
Set key C-z to command:...
And now the standard default is returned to by doing
M-x global-set-key M-del ...
backward-kill-word
But this is transient and must be done on each reload, any way to make this permanent?
Putting a command into the init.el is not overriding the other effect