all instances of the class are updated, which is more powerful than replacing. if you are curious to try it you can refer to the following https://lispcookbook

all instances of the class are updated, which is more powerful than replacing. if you are curious to try it you can refer to the following https://lispcookbook.github.io/cl-cookbook/clos.html#:~:text=To%20redefine%20a%20class%2C%20simply,to%20reflect%20the%20new%20definition https://lispcookbook.github.io/cl-cookbook/clos.html#:~:text....