> For the complete documentation index, see [llms.txt](https://emacs-lisp.ivory.cafe/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://emacs-lisp.ivory.cafe/lisp-shu-ju-lei-xing/bian-cheng-lei-xing/2.4.18-lei-xing-miao-shu.md).

# 2.4.18 类型描述符

类型描述符（type descriptor）是一种记录(record)，其中描述了某个类型的信息。记录的第一个槽是一个符号，这个符号表示了这个新类型的名称。而type-of 函数就是从这里获得的类型的信息。余下的槽都不被 Emacs 使用；它们可以用来拓展 Lisp。

类型描述符是 cl-sreucture-class 的实例。


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