: ) wonderful world ( :

(defun compose (&rest funs)
  (if (null funs)
      (lambda (k) k)
      (lambda (k)
	(funcall (car funs)
		 (funcall (apply #'compose (cdr funs)) k)))))

CL-USER> (funcall (compose (lambda (k) (* k 2)) (lambda (k) (sqrt k))) 2)
2.828427
CL-USER> (funcall (compose (lambda (k) (* k 2))) 2)
4
CL-USER> (funcall (compose) 2)
2
CL-USER>