common lisp 的函数 CLASS-OF

class-of.txt

语法
  class-of object => class
  
参数和值
  object --- 一个 object
  class --- 一个 class object

描述
  返回 object 的类, 其中object 是这个类的直接实例

代码
  * (class-of 'fre) 
  #<BUILT-IN-CLASS SYMBOL>

  * (class-of 2/3)
  #<BUILT-IN-CLASS RATIO>

  * (defclass book () ())
  #<STANDARD-CLASS BOOK>

  * (class-of (make-instance 'book))
  #<STANDARD-CLASS BOOK>

  * (defclass novel (book) ())
  #<STANDARD-CLASS NOVEL>

  * (class-of (make-instance 'novel))
  #<STANDARD-CLASS NOVEL>