re: Issue: PEEK-CHAR-READ-CHAR-ECHO (Version 3)

[Kim A. Barrett <IIM@ECLA.USC.EDU>]

However, I think it should be mentioned that this implies that PEEK-CHAR is
really no longer equivelent to read-char followed by unread-char, and can't be
implemented that way for any kind of metastream.  All metastreams must now
support PEEK-CHAR directly, and pass it along to the indirect streams, in case
some of those streams are echo streams.  This mostly increases the cost to
implementors, though it is also a cost to users in systems where the set of
metastreams is user-extensible.