Jeremy Shute wrote me to say that he like the idea of my Cog code generator enough to reimplement it in Perl: PCG :: The Perl Code Generator.

Jeremy also sent along an elisp snippet to get Emacs to run Cog interactively, handy during development of the code generators:

;; COG stuff.
(defun cog-buffer ()
  (interactive)
  (save-buffer)
  (call-process "cog.py" nil "*Messages*" nil "-r" (buffer-file-name))
  (revert-buffer nil t))
(global-set-key [f5] 'cog-buffer)