recognizer for the empty list
Major Section:  ACL2-BUILT-INS

Null is the function that checks whether its argument is nil. For recursive definitions it is often preferable to test for the end of a list using endp instead of null; see endp.

Null is a Common Lisp function. See any Common Lisp documentation for more information.

To see the ACL2 definition of this function, see pf.