Readtables and prin1

["Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU>]

OK, apparently lots of systems peek at the current readtable in order to
see which characters need to be slashified (or vertical-barred) on
output.  That's probably impossible to get right, if by "right" you mean
doing the minimal slashification that is necessary but no more.
However, it doesn't hurt to slashify extra characters if there is some
doubt.  I'm not sure whether I think this is valuable or important, but
I won't argue against it.

I still think that requiring PRIN1 to perform correctly given any
arbitrary readtable is much too hard to make this a required part of the
language, and probably impossible.  I'm not sure whether a half-assed
attempt to adapt to the current readtable is better than explicitly not
doing this at all.  My inclination would be to require anyone using an
extensively hacked readtable to write his own matching printer.

-- Scott