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Function LISTP

Syntax

  • listp objectgeneralized-boolean

Arguments and Values

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

Side Effects

None.

Affected By

None.

Exceptional Situations

None.

See Also

Example Implementation

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

Notes

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