[kazinator]

Author here. Currently working on a debugger. (Threw the old crappy one out.) Backtraces are working. Some of the remaining work is going to require long, uninterrupted concentration that is hard to come by due to taking care of a six-month-old baby.

I have over 50 unreleased patches. There are some bugfixes, including a compiler one, involving dynamically scoped variables used as optional parameters:

      (defvar v)
      (defun f (: (v v)))
      (call (compile 'f)) ;; blows up in virtual machine with "frame level mismatch"

Patch for that:

  diff --git a/share/txr/stdlib/compiler.tl b/share/txr/stdlib/compiler.tl
  index e76849db..ccdbee83 100644
  --- a/share/txr/stdlib/compiler.tl
  +++ b/share/txr/stdlib/compiler.tl
  @@ -868,7 +868,7 @@
                                       ,*(whenlet ((spec-sub [find have-sym specials : cdr]))
                                           (set specials [remq have-sym specials cdr])
                                           ^((bindv ,have-bind.loc ,me.(get-dreg (car spec-sub))))))))))
  -                 (benv (if specials (new env up nenv co me) nenv))
  +                 (benv (if need-dframe (new env up nenv co me) nenv))
                    (btreg me.(alloc-treg))
                    (bfrag me.(comp-progn btreg benv body))
                    (boreg (if env.(out-of-scope bfrag.oreg) btreg bfrag.oreg))

There is now support in the printer for limiting the depth and length.

I added a derived hook into the OOP system; a struct being notified that it is being inherited.