14.2.6 consp [Function]

consp object ⇒ generalized-boolean

Arguments and Values::

object—an object.

generalized-boolean—a generalized boolean.

Description::

Returns true if object is of type cons; otherwise, returns false.

Examples::

 (consp nil) ⇒  false
 (consp (cons 1 2)) ⇒  true

The empty list is not a cons, so

 (consp '()) ≡ (consp 'nil) ⇒  false

See Also::

listp

Notes::

 (consp object) ≡ (typep object 'cons) ≡ (not (typep object 'atom)) ≡ (typep object '(not atom))