ENDP.html -- ACL2 Version 6.3

### ENDP

recognizer for empty lists

    Major Section:  ACL2-BUILT-INS

In the ACL2 logic, `(endp x)` is the same as `(atom x)`. See atom.

Unlike `atom`, the guard for `endp` requires that `x` is a `cons` pair or is `nil`. Thus, `endp` is typically used as a termination test for functions that recur on a `true-listp` argument. See guard for general information about guards.

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

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