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listp (Function)

Syntax:
— Function: listp object generalized-boolean
Arguments and Values:

object—an object.

generalized-boolean—a generalized boolean.

Description:

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

Examples:
 (listp nil)  true
 (listp (cons 1 2))  true
 (listp (make-array 6))  false
 (listp t)  false
See Also:

consp

Notes:

If object is a cons, listp does not check whether object is a proper list; it returns true for any kind of list.

 (listp object) ≡ (typep object 'list) ≡ (typep object '(or cons null))