# 4.2 谓语：字符串相关

查阅 序列数组 向量以及向量章节，查阅更多关于底层 通用序列 及 数组 谓语。

Function: stringp object\
  如果 object 为字符串，则返回 t，否则返回 nil。

Function: string-or-null-p object\
  如果 object 为字符串，或 nil，则返回 t，否则返回 nil。

Function: char-or-string-p object\
  如果 object 为字符或字符串，则返回 t，否则返回 nil。


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