How to auto highlight the current word in vim? - vim

Question

For example, our text is:
hello world
abcd hello world
hello world
In eclipse, when your cursor is at some word, the word hello is auto highlight in the current file. When you type ww in normal mode, the cursor is at other word world will highlight in the current file, the hello is un-highlighted automatically. This feature is very convenient for users.
Does vim can do this with some plugin or else?

Answer 1

Something like this?
set updatetime=10
function! HighlightWordUnderCursor()
if getline(".")[col(".")-1] !~# '[[:punct:][:blank:]]'
exec 'match' 'Search' '/\V\<'.expand('<cword>').'\>/'
else
match none
endif
endfunction
autocmd! CursorHold,CursorHoldI * call HighlightWordUnderCursor()
This won't clobber the search register but will use the same highlighting as would normally be used. (If you want a different highlight color change Search to that highlight group.) A short update time is needed so that the CursorHold event it fired fairly often. It also won't highlight anything if the cursor is above punctuation or whitespace.
The iskeyword setting determines what is considered part of a word when expand('<cword>') is used.

Answer 2

Improving #FDinoff's amazing answer, with custom highlight - dark BG and underline, and disable on quickfix list, fugitive filetype and when on diff:
function! HighlightWordUnderCursor()
let disabled_ft = ["qf", "fugitive", "nerdtree", "gundo", "diff", "fzf", "floaterm"]
if &diff || &buftype == "terminal" || index(disabled_ft, &filetype) >= 0
return
endif
if getline(".")[col(".")-1] !~# '[[:punct:][:blank:]]'
hi MatchWord cterm=undercurl gui=undercurl guibg=#3b404a
exec 'match' 'MatchWord' '/\V\<'.expand('<cword>').'\>/'
else
match none
endif
endfunction
augroup MatchWord
autocmd!
autocmd! CursorHold,CursorHoldI * call HighlightWordUnderCursor()
augroup END

Answer 3

Yes there is a vim plugin for highlighting the occurances of a word automatically. This one is implemented exclusively for $variables and ->properties in .php files.
DEMO :
And here is the same one but adapted for Perl files.
DEMO :
May be you can modify it for your purpose.

Answer 4

There's a script on vim.wikia.com for doing exactly that. It waits until you've stopped moving the cursor and then highlights all instances of the current word. You can then use n and N to jump between them like you normally would with search results.
I'm copying it here in case the link goes down:
" Highlight all instances of word under cursor, when idle.
" Useful when studying strange source code.
" Type z/ to toggle highlighting on/off.
nnoremap z/ :if AutoHighlightToggle()<Bar>set hls<Bar>endif<CR>
function! AutoHighlightToggle()
let #/ = ''
if exists('#auto_highlight')
au! auto_highlight
augroup! auto_highlight
setl updatetime=4000
echo 'Highlight current word: off'
return 0
else
augroup auto_highlight
au!
au CursorHold * let #/ = '\V\<'.escape(expand('<cword>'), '\').'\>'
augroup end
setl updatetime=500
echo 'Highlight current word: ON'
return 1
endif
endfunction
As noted in a comment on that page, if you always want this feature on you can just call the function from your vimrc after defining it. That way you can use z/ (or whatever shortcut you assign it to) to turn it off again later.