These notes correspond to *pcl-system-date* "4/21/87 April 21rst 1987". The notes from the last release are stored as 3-19-notes.text This release runs in: ExCL Lucid Symbolics Common Lisp (Genera) Vaxlisp (2.0) Xerox Common Lisp (Lyric Release) Kyoto Common Lisp (5.2) CMU Lisp (nee Spice) should be working soon, I will announce another release at that time. Xerox Lisp users should FTP all the source files from /pub/pcl/ as well as all the dfasl files from /pub/pcl/xerox/. Included in the xerox specific directory is a file called PCL-ENV, which provides some simple environment support for using PCL in Xerox Lisp. The major difference in this release is that defclass conforms to the CLOS specification (pretty much I hope). Previous warnings about what would happen when defclass became CLOS defclass now apply. Once major difference is that PCL currently does require that all a classes superclasses be defined when a defclass form is evaluated. This will change sometime soon. Other small changes include: Some more of the files have been renamed and restructured (as promised). the defclass parsing protocol has changed slotd datastructures are now instances of the class standard-slot-description. a performance bug in the ExCL port which causes method lookup and slot access to cons needlessly. a bug in the 3600 port which broke the printer for stack consed closures make-specializable a bug in Lucid lisp which made it impossible to say (compile-pcl) has been patched around, this is the bug that manifested itself as NAME being ubound. As usual, please enjoy and send comments.