🚀 go-pugleaf

>>>>> On Mon, 9 Nov 1992 05:18:53 GMT, george@hsvaic.boeing.COM (George Williams) said:

   George> On Nov 9,  3:49pm, Eric Peterson x7644 wrote:
>    Jeffrey> (defclass test-class ()
>    Jeffrey> 	((slot-1	:initarg :slot-1
>    Jeffrey> 		:initform 1
>    Jeffrey> 		:accessor slot-1)
>    Jeffrey> 	(slot-2	:initarg :slot-2
>    Jeffrey> 		:initform ?????      ; <- The question
>    Jeffrey> 		:accessor slot-2)))
> 
>    Jeffrey> The problem is that I need for slot-2 to default to the same value as
>    Jeffrey> slot-1 if the user does not specify it in the constructor.
> 
> I believe the following will do what you want provided that you are
> willing to call with :slot-2 first when both initargs are used (see
> CLtL2 28.1.9.4. first paragraph after the last bullet):
> 
> (defclass test-class ()
>   ((slot-1 :initarg :slot-1
>            :initform 1
>            :accessor slot-1)
>    (slot-2 :initarg :slot-1 :initarg :slot-2 
>            :accessor slot-2)))
> 
> 
> Required call order for non-defaulting case:
> 
> (make-instance 'test-clas :slot-2 5 :slot-1 3 )

   George> I don't mean to start a flame war, but I sure wouldn't want to maintain
   George> this kind of code.

   George> --george