cond-expandclause did not work as R7RS requires.
runprocedure crushed on Linux.
change-classhas been supported.
-Soption has been added to handle other library suffixes.
- Class object now has 'direct-subclasses' slot.
- R7RS style srfi library names are supported.
- Compiler now eliminate some of referencial transparent expressions if it can.
- Build process has been changed.