I'd like to add a postscript to the preceding: this is not set in#

Sat Feb 19 02:44:32 2005

I'd like to add a postscript to the preceding: this is not set in stone. (1) I'll probably hack it for some looser equality predicate than EQ. (2) To cope with uses like (incf (ref thing :el)) it would be very nice to pass an optional default. Now is however not the time to decide which arg the default will be, but it's looking kind of non-obvious at present.