unclarities: defstruct print functions

[Rob MacLachlan <RAM@C.CS.CMU.EDU>]

    Another issue in need of resolution is that of communicating the
current depth in the printing when there are user-defined print
functions.  Guy said that what had in mind was that the user would
bind *print-level* according to the depth arg supplied to the print
function, but there were several problems with this.  Most of the
tasteful solutions involved adding new args to WRITE which indicated
the nature of the recursive use of the printer.  Others objected that
nobody uses WRITE, so that isn't a real fix.

    This was discussed about a month ago.  Only God knows how many
unresolved issues lie buried and forgotten in the Common Lisp archive.

  Rob