This vim plugin seems to do most of what you describe by wrapping the matchadd() vimscript function: http://www.vim.org/scripts/script.php?script_id=2666 http:

This vim plugin seems to do most of what you describe by wrapping the matchadd() vimscript function: http://www.vim.org/scripts/script.php?script_id=2666 http://www.vim.org/scripts/script.php?script_id=2666 <Leader>r (regex) to add matches to the set of highlighted groups.