TAB to update anything candidates without delay

anything-update-or-select-action.el

(defun anything-update-or-select-action ()
  "Immediately update anything candidates without delay.
If invoked twice in a row, does anything-select-action"
  (interactive)
  (if (eq last-command 'anything-update-or-select-action)
      (anything-select-action)
    (anything-check-new-input (minibuffer-contents))))

(mapc #'(lambda (sym)
          (let ((map (and (boundp sym) (symbol-value sym))))
            (and map
                 (mapc #'(lambda (key)
                           (if (eq (lookup-key map key) 'anything-select-action)
                               (define-key map key 'anything-update-or-select-action)))
                       (list "\C-i" (kbd "<tab>"))))))
      '(anything-map anything-c-bookmark-map anything-c-buffer-map
                     anything-c-etags-map anything-c-grep-map anything-c-pdfgrep-map
                     anything-c-read-file-map anything-c-ucs-map
                     anything-esh-on-file-map anything-eval-expression-map
                     anything-find-files-map anything-generic-files-map))