#!/usr/local/bin/sbcl --script


(format t "~a~%"(remove-if-not #'evenp '(1 2 3 4 5 6 7 8 9 10)))
(remove-if-not #'evenp '(1 2 3 4 5 6 7 8 9 10))



(format t "~a~%" (remove-if-not #'(lambda (x) (= 0 (mod x 2))) '(1 2 3 4 5 6 7 8 9 10)))


(format t "~a~%" (remove-if-not #'(lambda (x) (= 1 (mod x 2))) '(1 2 3 4 5 6 7 8 9 10)))








(defun make-cd (title artist rating ripped)
  (list :title title :artist artist :rating rating :ripped ripped))

(defvar *db* nil)
(defun add-record (cd) (push cd *db*))

(add-record (make-cd "Roses" "Kathy Mattea" 7 t))
(add-record (make-cd "Fly" "Dixie Chicks" 8 t))
(add-record (make-cd "Home" "Dixie Chicks" 9 t))

(defun dump-db ()
  (dolist (cd *db*)
    (format t "~{~a:~10t~a~%~}~%" cd)))

(dump-db)





(defun select-by-artist (artist)
  (remove-if-not
   #'(lambda (cd) (equal (getf cd :artist) artist))
   *db*))

(defun select (selector-fn)
  (remove-if-not selector-fn *db*))

(defun artist-selector (artist)
  #'(lambda (cd) (equal (getf cd :artist) artist)))

(format t "~a~%" (select (artist-selector "Dixie Chicks")))