Mapping <esc> in vimrc causes bizarre arrow behaviour
vim
Solution
The mapping
nnoremap <esc> :noh<return><esc>
will conflict with so called "grey keys" and I believe that it should be used either in GVim only or in terminal Vim by someone who does not use special keys like arrows.
From what I know (and guess) how Vim processes keys, I would say that it's impossible to do anything with this. For Vim to recognize special key all its components should go in a row, so when you press Arrow Left Vim gets the following sequence of codes:
<esc> [ D
But after your mapping Arrow Left becomes:
: n o h l <cr> <esc>
[ D
Vim sees two separate sequences and treats <esc> as a single press of Escape key, thus next two codes of Left Arrow key lose their special meaning.
So I suggest you to map `:noh` to some other key sequence (e.g. to one starting with `<leader>`, see `:help mapleader`; I don't recommend you to use F-keys, using them is as bad as using of arrow keys).
Problem
I am a happy VIM user, although I admit I'm quite far from being fluent. I found this nice post: Vim clear last search highlighting and I thought I'd become a better person if I didn't have to hammer away a random character sequence every time I did a search. Now, I'm also using the vimrc config from here: http://amix.dk/vim/vimrc.html and the problem I have is that when I add the line `nnoremap <esc> :noh<return><esc>` to it (it doesn't seem to make a difference where I put it) I get awkward behaviour when I use arrows in command mode, namely letters from A to D appear in a newline and I get switched to insert mode. There has to be some mapping conflict but for the life of me I can't figure out where it is. EDIT: As it follows from the answers it turns out the Ultimate vimrc part is not relevant, the mentioned `nnoremap` command will cause altered arrow behaviour even if it's the only vimrc entry. Changing title to a more informative one. PS. I know I shouldn't use arrows, hopefully I'll get there one day.