I use the XP package to implement that part of the ANSI standard
described in
22.3.5 FORMAT Pretty Printer Operations
which can be found at
http://www.harlequin.com/books/HyperSpec/Body/sec_22-3-5.html
or in
Common Lisp the Language, 2nd Edition. Chapter 27. Pretty Printing
at
http://www.cs.cmu.edu/Web/Groups/AI/html/cltl/clm/node253.html
I use the XP code on both GCL and CLISP and it works very well according
to spec with one exception. On both of these lisps evaluation of the form:
(format t "~?" "~_" nil)
gives an error. In general, use of ~? and other pretty printing
directives causes an error or non-standard behavior. Apparently
the recursive call to format does not know that it should be redefined
by the XP definition of format.
Has anyone else experienced this? Has anyone solved it?
It's possible that I haven't properly loaded XP, so if anyone does
not get the behavior I described, please let me know.
Thanks.
--
Benjamin Shults Email: ·······@math.utexas.edu
Department of Mathematics Phone: (512) 471-7711 ext. 208
University of Texas at Austin WWW: http://www.ma.utexas.edu/users/bshults
Austin, TX 78712 USA FAX: (512) 471-9038 (attn: Benjamin Shults)