The next Pixie Scheme release (if there is one) will probably be an upgrade to the "R4" ("Revised revised revised revised╔) Scheme language standard, involving at least moderate changes in what the built╨in procedures are and how they are implemented. The official "R4" report was due out in October, 1990, but as of 1 January 1991, I haven't seen it yet, so I can't say when the next Pixie Scheme release might happen.
Fair warning: The "R4" standard is reported to require that the empty list, (), *NOT* act like the false boolean, #f, when used where a boolean is expected. That is, in R4 Scheme
(if '() 'true 'false) ==> true,
whereas in R3 Scheme ╤ and thus in all releases of Pixie Scheme to date ╤ and in most other Lisps that have ever existed,
(if '() 'true 'false) ==> false.
Much Lisp and Scheme code will break when this change happens. Be warned.
Likely enhancements of my own ╤ not part of whatever R4 may contain ╤ include more file and more I/O procedures, and perhaps a pure functional subset of the language itself.
Wilder dreams include Logo╨like turtle graphics, means to evaluate an expression in an environment of the user's choice, and a foreign╨function interface.
