Re: CHANGE-CLASS not implemented?

[syali@cs.Buffalo.EDU (Sy Ali)]

	From clisp-list@ma2s2.mathematik.uni-karlsruhe.de Mon Sep 20 10:30:32 1993
	Date: Mon, 20 Sep 93 16:27:35 +0200
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	From: haible@ma2s2.mathematik.uni-karlsruhe.de (Bruno Haible)
	To: Multiple recipients of list <clisp-list@ma2s2.mathematik.uni-karlsruhe.de>
	Subject: Re: CHANGE-CLASS not implemented?

	Sy Ali <syali@cs.Buffalo.EDU> asks:

	> Is this not implemented in the latest version of CLISP?

	No, I didn't implement CHANGE-CLASS. It is hardly ever used, and it violates
	a fundamental property of Lisp: an object's type must be constant as time
	passes.
	(Would you be happy if a string could be "changed" to become a number?)

	If you really need CHANGE-CLASS, you may use PCL. It's bigger and slower
	than CLISP's native CLOS, but it has CHANGE-CLASS.


	                    Bruno Haible
	                    haible@ma2s2.mathematik.uni-karlsruhe.de


---

I'm familiar with all the above arguments. I'm also capable of writing
a CHANGE-CLASS of my own.

I was just wondering if this was an oversight on your part, since it is
part of the specification. It's your lisp (which I'm happy for) and you
can decide if you want to be conformant or not.

Thanks, Sy