Highlighting color strings with correspondent color

Question

When tweaking color themes, one thing I really miss is a highlighting that would color the color strings with the corresponding color.

Maybe this sounds confusing? An example: here is a fragment of a Vim theme:

hi Constant    ctermfg=Magenta      guifg=Magenta
hi Special     ctermfg=Red          guifg=Red
hi Identifier  ctermfg=Cyan         guifg=Green

I would like to have a syntax highlight that would color Magenta in magenta, Red in red, and so on, similar to what happens with color codes for dircolors file:

01;34 is the color code for blue, thus Vim displays it in blue, 01;36 is cyan, etc.

I searched into the syntax directory for files with "color" in their name,

$ find . -iname '*color*'
./colortest.vim
./dircolors.vim
./syncolor.vim

but none of these do the job for the color strings.

Am I missing some resource or do I have to create my own syntax file?

Answer 1

There are a number of plugins that do this for colour names, hex colours, and RGB colours:

• Colorizer by Christian Brabandt, (who appears to be modestly refraining from answering this question with a link to his own plugin),
• Coloresque by Konstantin,
• vim-css-color by Aristotle Pagaltzis,
• vim-css-color (a different one) by Max Vasiliev