RosettaCodeData/Task/Church-numerals/Common-Lisp/church-numerals-4.lisp
2023-09-16 17:28:03 -07:00

5 lines
177 B
Common Lisp

(defmacro church-if (test then else)
`(funcall ,test (lambda () ,then) (lambda () ,else)))
(defvar true (lambda (f g) (funcall f)))
(defvar false (lambda (f g) (funcall g)))