[emacs] Best(?) way to go to a function/variable's declaration (within buffer)

anything-goto-symbol

(defun anything-goto-symbol ()
  "Show anything list, using current symbol as input to narrow the choices."
  (interactive)
  (anything
   :prompt "Go to:"
   :candidate-number-limit 10
   :input (thing-at-point 'symbol)
   :sources
      '( anything-c-source-imenu
         anything-c-source-browse-code
         anything-c-source-semantic
        ;; anything-c-source-info-emacs-lisp-intro
         )))