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  ANSI Common Lisp   14 Conses   14.2 Dictionary of Conses

14.2.17 listp Function

Syntax:
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))

Allegro CL Implementation Details:
None.

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