Add an option to only take effect on specific filetypes

README.md

@@ -62,6 +62,13 @@ Disabling this option will make the word highlight persist over window switches
 let g:vim_current_word#highlight_only_in_focused_window = 1
 ```
 
+##### Whitelist filetypes:
+
+To allow only in specific filetypes, add this variable to your vimrc:
+```vim
+let g:vim_current_word#included_filetypes = ['ruby']
+```
+
 ##### Blacklist filetypes:
 
 To avoid specific filetypes, add this variable to your vimrc:

autoload/vim_current_word.vim

@@ -19,7 +19,14 @@ endfunction
 function! vim_current_word#pre_highlight()
   call vim_current_word#clear_current_word_matches()
   let l:vim_current_word_disabled_in_this_buffer = get(b:, 'vim_current_word_disabled_in_this_buffer', 0)
-  if !g:vim_current_word#enabled || index(g:vim_current_word#excluded_filetypes, &filetype) >= 0 || l:vim_current_word_disabled_in_this_buffer | return 0 | endif
+if !g:vim_current_word#enabled || index(g:vim_current_word#excluded_filetypes, &filetype) >= 0 || l:vim_current_word_disabled_in_this_buffer || (len(g:vim_current_word#included_filetypes) > 0 && index(g:vim_current_word#included_filetypes, &filetype) == -1)
+  return 0
+end
+  if len(g:vim_current_word#included_filetypes) > 0
+      if index(g:vim_current_word#included_filetypes, &filetype) == -1
+          return 0
+      end
+  end
   if g:vim_current_word#highlight_delay
     call vim_current_word#schedule_highlight()
   else

plugin/vim_current_word.vim

@@ -7,6 +7,7 @@ let g:vim_current_word#highlight_current_word = get(g:, 'vim_current_word#highli
 let g:vim_current_word#highlight_only_in_focused_window = get(g:, 'vim_current_word#highlight_only_in_focused_window', 1)
 let g:vim_current_word#highlight_delay = get(g:, 'vim_current_word#highlight_delay', 0)
 let g:vim_current_word#excluded_filetypes = get(g:, 'vim_current_word#excluded_filetypes', [])
+let g:vim_current_word#included_filetypes = get(g:, 'vim_current_word#included_filetypes', [])
 
 augroup vim_current_word
   autocmd!