Toggle highlighting current word

toggle-highlight-word.el

(require 'hi-lock)

(defun toggle-highlight-word ()
  (interactive)
  (let ((regex (concat "\\_<" (current-word) "\\_>")))
    (if (member regex (mapcar #'car hi-lock-interactive-patterns))
        (unhighlight-regexp regex)
      (highlight-symbol-at-point))))

(defun unhighlight-all-highlighted-words ()
  (interactive)
  (let ((hi-regexs (mapcar #'car hi-lock-interactive-patterns)))
    (mapcar (lambda (regex) (unhighlight-regexp regex)) hi-regexs)))

(global-set-key [f9] 'toggle-highlight-word)
(global-set-key [S-f9] 'unhighlight-all-highlighted-words)