don't block vim while listing tags

Examples.md

@@ -304,14 +304,15 @@ Jump to tags
 ---
 
 ```vimL
-function! TagList()
-  return map(taglist('.*'), 'v:val["name"]')
+function! TagCommand()
+  return substitute('awk _!/^!/ { print \$1 }_ ', '_', "'", 'g')
+              \ . join(tagfiles(), ' ')
 endfunction
 
 command! FZFTag call fzf#run({
-\   'source'     : TagList(),
+\   'source'     : TagCommand(),
 \   'sink'       : 'tag',
-\   })
+\   })<CR>
 ```
 
 Fuzzy cmdline completion