reference to documentation

[Emanuel Berg]

(require 'man)

(defun man-kill-reference ()
  (interactive)
  (let ((page (car (split-string Man-page-mode-string))))
    (when (and (stringp page)
               (not (string-empty-p page)) )
      (let ((page-dc (downcase page)))
        (kill-new page-dc)
        (message page-dc) ))))

;; all source:
;;   https://dataswamp.org/~incal/emacs-init/man-incal.el

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