transcendental-lisp/lisp/lang/functions.lisp

40 lines
1.1 KiB
Common Lisp

(defun mapcar (function-name the-list)
(if the-list
(cons
(funcall function-name (first the-list))
(mapcar function-name (rest the-list)))))
(defun maplist (function-name the-list)
(cond
((null the-list) nil)
(t (cons (funcall function-name the-list)
(maplist function-name (rest the-list))))))
(defun append (list-one list-two)
(append-tail (reverse list-one) list-two))
(defun append-tail (reversed-list list-two)
(if (null reversed-list) list-two
(recur (rest reversed-list) (cons (car reversed-list) list-two))))
(defun reverse (the-list)
(reverse-tail () the-list))
(defun reverse-tail (accumulator the-list)
(if (null the-list) accumulator
(recur (cons (first the-list) accumulator) (rest the-list))))
(defun deep-reverse (the-list)
(if the-list
(append
(deep-reverse (rest the-list))
(list
(if (listp (first the-list))
(deep-reverse (first the-list))
(first the-list))))))
(defun nth (n listA)
(cond
((equal 0 n) (first listA))
(t (nth (- n 1) (rest listA)))))