《通链参考手册》


Function LISTP

●语法设定:

listp object => generalized-boolean

●参数和值:

object---an object.

generalized-boolean---a generalized boolean.

●详情:

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

●例子:

 (listp nil) =>  true
 (listp (cons 1 2)) =>  true
 (listp (make-array 6)) =>  false
 (listp t) =>  false

●副作用: None.

●受制于: 无。

●例外情况: 无。

●更多信息:

consp

●说明:

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))


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