coupling from filename

coupling.el

;; coupling.el
;; written by oh_cannot_angel
;;
;;; Installation:
;;
;; Put the coupling.el to your load-path.
;; Add to init.el or .emacs:
;; (require 'coupling)
;; (coupling-source-directory)
;; (global-set-key (kbd "C-c b") 'coupling-from-directory)

;; M-x Neco runs Neco. Try it!
;; coupling.el

;; default coupling-source-directory
(setq coupling-source-directory "~/.emacs.d/elisp")

(defun create-coupling-source-list ()
  (delq nil (mapcar
	     (lambda (s)
	       (when (string-match "\\(.+\\)\\..+" s)
		 (match-string 1 s)))
	     ;; file-list)))
	     (directory-files coupling-source-directory))))

(defun coupling-from-list (lst)
  (let* ((seme (random-select lst))
	 (uke (random-select (delq seme lst))))
    (message "%s × %s" seme uke)))

(defun random-select (lst)
  (cond ((null lst) nil)
	((nth (random (length lst)) lst))))

(defun coupling-from-directory ()
  (interactive)
  (let* ((l (create-coupling-source-list)))
    (when l
      (coupling-from-list l))))

(provide 'coupling)