Can I map Alt key in Vim?

Question

I tried to map <Alt+D> to <Ctrl+D> by adding the below line to .vimrc, but it doesn't work. I checked the .vimrc is loaded by Vim.

map <Alt-D> <C-D>

Is there any error in this mapping?

Calumniate

Are you using vim in a terminal, or a gui version (gvim, macvim)? – Abirritant

Also note that if your encoding changes after the mapping runs, what you get out of your Alt keys may not match what you initially set. – Aboveground

In insert mode, press control+v, then your key combo alt+d & it should insert ^[d. So you end up with map ^[d <C-D> or what have you. Note that TYPING ^[d does not do the same thing. – Finned

Your Operating system or Terminal Emulator (or maybe both) has intercepted your Alt-d keystroke and performed an action that produced no visible change (New-Bookmark?). Find your OS system settings->keymaps tool and remove all keymaps associated with Alt-d. Again do this with keybindings defined in your Terminal settings->keymaps. Now vim is able to receive your Alt-d. – Spacious

Answer 1

To Mac users out there: for mapping ALT+hjkl, use instead the real character generated (find out which character using the combination while in INSERT mode), for example with my keyboard I get:

<ALT+j> ==> ª
<ALT+k> ==> º

and so on. Solution found here on StackOverflow.

I used this to move lines up and down with ALT+k\j, using this on my .vimrc:

nnoremap ª :m .+1<CR>==
nnoremap º :m .-2<CR>==

inoremap ª <Esc>:m .+1<CR>==gi
inoremap º <Esc>:m .-2<CR>==gi

vnoremap ª :m '>+1<CR>gv=gv
vnoremap º :m '<-2<CR>gv=gv

as explained here.

Hope it's useful, enjoy Vim :)

ADDENDUM BY Dylan_Larkin (2019): For this to work on a Mac, "Use Option as Meta Key" must be turned OFF in Terminal->Preferences->Keyboard

UPDATE 09/2021

I recently switched from a "British" keyboard to "ABC - Extended" and noticed this configuration doesn't work as expected. As an alternative, I mapped the <up> and <down> keys to do the same operation (which, I guess, also solves most of the complexity explained in other answers of this very question):

nnoremap <down> :m .+1<CR>==
nnoremap <up> :m .-2<CR>==

inoremap <down> <Esc>:m .+1<CR>==gi
inoremap <up> <Esc>:m .-2<CR>==gi

vnoremap <down> :m '>+1<CR>gv=gv
vnoremap <up> :m '<-2<CR>gv=gv

This is also a great way for beginners to rewire the habit of using the arrows and instead learn the much more efficient Vim motion way to move around the code. ;)

You can complete your transition mapping <left> and <right> to quickly move between tabs with:

nnoremap <left> gT
nnoremap <right> gt

Or whatever you fancy (even a brutal <NOP>, like I did at the beginning of my journey).

Piggy

This is just what I came here for (Alt+HJKL to move splits)! Thanks! – Irksome

A easy way to find out which character it is, is by using cat. Simply type cat and inside the cat window the key combination you want. Found out that alt + brackets is ‘ and “ on my mac. – Alvin

this works great as Alt+HJKL to move between splits, my fingers love it!! nmap ˙ <C-w><Left> nmap ¬ <C-w><Right> nmap ˚ <C-w><Up> nmap ∆ <C-w><Down> – Sea

As wacky as it sounds, this is actually correct. Thanks bunches! – Varuna

The question has nothing specified as having to do with Mac, so why is this Mac-specific answer so up-voted and accepted? The original question is an important one that affects many OSs and terminals, so a more generic answer like that from @pablox should be favored. – Cronyism

@MicahElliott: I actually agree with you, but bare in mind that his question is almost 2 years younger and mine was actually just an addendum for Mac users: the question was already answered, I don't know why it's now accepted. Anyway, the nice thing about SO is that pablox's answer is here, everybody can read it, and if somebody find it relevant can up-vote it (as I just did, BTW). At the end of the day, the only thing that really count is to help each other. :) – Piggy

These exact mappings may not work as expected in future versions of OSX. Use sed -n l to see the output of <A-k> and <A-j> before you configure the mapping. In my case <A-j> is ∆ and <A-k> is ˚ – Puzzlement

This only seems to work on MacVim. It does not seem to work from terminal Vim on OS X. – Enkindle

@AlistairMacDonald : although I am using MacVim, I just tested on my terminal (iTerm and Terminal, just to be sure) and it seems to work fine.... ¯_(ツ)_/¯ – Piggy

¯_(ツ)_/¯ foobar – Enkindle

So @AlistairMacDonald did you find a solution in the end? :) – Piggy

I did. Use the CTL key. – Enkindle

proper way in macvim: set macmeta in .vimrc enables mapping the alt key – Daubigny

Alt j is ∆ and alt k is ˚ for me, When I save this in my .vimrc I get a conversion error. I have a set encoding=utf-8 in my .vimrc and it doesnt help. I was able to save doing this :w ++enc=utf-8 but when i reopen the symbol changes to an upside down question mark :( – Desmonddesmoulins

I'm not sure what's happening @av4625, encoding always confuse me! Check if your encoding is actually set with :set encoding? (sometime a typo can mess your life!), then try with a new fresh .vimrc, adding only the relevant lines, so you can be assured no other command of plugin is messing up your configuration mid-way. Also, take a look at your terminal emulator configuration and make sure everything is set as it should be (I found this not to be the case, sometimes). Hope this helps, let me know and good luck! :) – Piggy

On macOS, when setting Use Option as Meta Key or on iTerm profile ⌥ key to Esc+ will behave as the traditionally way (like on Linux/Unix). So you don't need to set on Vim the map to <^[j>, just map it to <A+j> or <M+j> and it works. – Coblenz

Thank you @goetzc, somebody edited my answer adding the last sentence: I didn't check the functionality and trusted the user, but he was probably wrong. I'm going to remove it from my answer and add it as a comment (for reference) – Piggy

QUESTION BY @Dylan_Larkin: For this to work on a Mac, "Use Option as Meta Key" must be turned OFF in Terminal->Preferences->Keyboard Note that with this option ON, on more recent Mac OS', Alt+j is ^[j. However, and YMMV, but trying to map ^[j doesn't work for me. So, it's a trade-off, as I prefer Option as Meta Key=ON. If someone can find an updated solution (2017-19), that would be great. – Piggy

Quick note, unless I'm missing something, doing this would make it harder to find a mapping much later when using :verbose nmap <A-j> etc. – Deianira

FYI 'ª' if you paste it into vim, and press 'ga' it will show the character code as 170 or 0xaa. You can express it in vim as <char-170> or <char-0xaa> This allows you to map unusual keystrokes easily either by telling VIM which character represents down ( set <down>=<char-170>) or direct mapping (map <char-170> ....). Also, If you have UTF characters in your .vimrc, consider adding scriptencoding utf8 at the beginning. – Metalware

Use <A- or <M- notation… – Discriminate

Answer 2

:help key-notation describes what format needs to be used to map different keys. In the case of alt, you can use either <A- or <M-. So your mapping would be

map <M-d> <C-d>

I'd also recommend using the nore variant of :map (e.g., noremap) unless you explicitly want to allow the right-hand side to be re-evaluated for mappings.

Tallyman

This still doesn't have any effect. Alt+D input still inputs some strange character to Vim. – Calumniate

That's a separate issue. Your terminal is sending a multi-byte character to Vim and Vim doesn't know to interpret that as <A-d>. You probably need to change your terminal's settings so it sends <A-d> as <Esc>d. – Tallyman

@Tallyman how to do it on iterm2? – Harrod

@Tallyman Thanks. this key notation <A-j> works well in idea vim on Mac. – Extragalactic

Works in 2023 on neovim and NixOS 23.05 – Spann

Answer 3

I'm not sure is "possible" anymore. Please read the update below.

Yes, you can even in terminal vim, but there's no real catch all answer. You basically have to follow two steps:

1. Make sure the <M-d> notation exists, and map exactly what your terminal inputs (^[ is the escape character):

   $ cat
   ^[d
   $
   
   " in your .vimrc
   execute "set <M-d>=\ed"
   " you have to use double quotes!
   

2. Map something to your newly "created" combination:

   noremap <M-d> :echo "m-d works!"<cr>
   

Understanding how it works, you can expand this "trick" to other "strange" combinations, for instance, I'm using termite, and vim doesn't recognize <S-F1>, using cat I get ^[[1;2P. Then, in my vimrc I do: execute "set <S-F1>=\e[1;2P", and then I can map it to anything.

Note: I don't know why, but for some people using \<Esc> works instead of \e.

---

Update (february 2016)

Depending on the terminfo your terminal runs, maybe you could... in most terminals, "alt + h", for example, is mapped to ^[h, which is: "escape + h". So it could overwrite keys. I've just tried (again) and it seems to work, but I believe it's a very buggy and error prone implementation.

Nevertheless, for the brave enough, here's an experimental plugin:

• https://github.com/vim-utils/vim-alt-mappings
• https://github.com/drmikehenry/vim-fixkey

Landrum

Instead of the execute "set... stuff, you can just directly use set <M-d>=^[d. The ^[ is actually an escape character entered with C-v-Esc. This was necessary in rxvt/urxvt, but xterm shouldn’t need the special treatment. More info on this topic in the vim wiki. – Cronyism

Is there an analogous approach to this that would work with tmux so that i.e., M-d could be binded? – Stench

For me, <Esc> then d now does the same thing as <Alt>+d. Also, you can just do this in one line with Ctrl-v, <Esc> as per here. – Cherycherye

I've had issues with vim-move [1], but this finally fixed it -- thanks!! [1] github.com/matze/vim-move/issues/15 – Useful

Answer 4

Map Alt Key in Vim on Mac OSx:

Start by viewing the key code your terminal is sending to vim:

$ sed -n l
^[[1;9D 

In the above example, I ran the command and pressed Alt + Left.

The ^[[1;9D is the escaped sequence being sent to vim, so we can user that for our mapping.

map <Esc>[1;9D 

Amey

If you are using iTerm2 app, it is good to check how the keys are mapped in the Profile > Keys. – Eloisaeloise

With left Option key (⌥) configured as Esc+ in iTerm2, I could map alt+q to quit vim: nnoremap <silent> <Esc>q :qa!<cr> – Dareece

You can also setup iTerm2 to work with that remap if you go to Preferences > Profiles, select your current profile, go to the "keys" tab for that profile and change the option that says "Left ⌥ Key" to "Esc+" (available options are "Normal", "Meta", and "Esc+"). – Nut

Answer 5

Use:

map <A-D> <C-D>

See :help key-notation.

Schopenhauerism

It seems this still doesn't work. Alt+d will input an strange character to Vim, which is the same with the unmap case. – Calumniate

Works for me (I'm using gvim on Windows) – Footy

@Calumniate Your terminal/konsole GUI has intercepted your Alt-d and relayed a different keystroke that can be found by going to terminal->settings->keymaps. Your vim command is working perfectly, it's the keystroke that isn't getting past your terminal window. – Spacious

Answer 6

My Terminal would produce ^[x commands (e.g. for alt-x). What got it to work inside Vim was this small script from vim.wikia.com:

for i in range(97,122)
  let c = nr2char(i)
  exec "map \e".c." <M-".c.">"
  exec "map! \e".c." <M-".c.">"
endfor

Add to .vimrc to fix all alt key mappings.

Ellmyer

Answer 7

as a follow up to Bruno's answer for Mac users, try making sure your option key is mapped to Esc+.

This will give you the "normal" behavior of the option (A) key in Vim.

For example, in iterm2, this option can be found under Preferences > Profiles > Keys:

Aric

I also had to change the config to nnoremap <Esc>j :m .+1<CR>== and similar... – Intramuscular

Answer 8

Your terminal might not transmit "properly" the Alt-D. You can use C-V to actually get the actual escape sequence send to Vim and use it to create your mapping. Ie, edit your .vimrc and replace the actual by typing the following sequence "C-V Alt-D" so you'll have the correct escape sequence in your vimrc. That won't work if your terminal doesn't send anything to vim.

Distended

Answer 9

Find out key mapping by putting following command in your vim editor

:help key-notation

It will display all the key mapping.

In my ubuntu system for Alt it is <M-...>. It is possible for your version mapping might be different. If you too have same mapping then following should work.

map <M-D> <C-D>

Stuckup

Answer 10

Hello after no good solution after years of testing all the above on mac, I kept searching.

Here is my solution:

To create a combination keystroke including Alt you have to declare the combination in the preference > keyboard and use that combination in the vim setup file (check use option as meta key).

The output must be an unusual character (no a for example) so that you're not overriding a regular character.

In the example below you should be able to quite vim with ALT-Up.

vim setting:

mac setting:

Bellerophon

Answer 11

Another good option in 2024 for MacOS is to first disable international character support for the Option key; if that is acceptable, you can check out the solution here How to disable generating special characters when pressing the `alt+a`/`option+a` keybinding in Mac OS (`⌥+a` )?

Once that is done, set your terminal (e.g. iTerm2) to Esc+. Now the shortcuts will work.

Acrobatics