Issue: HASH-TABLE-PACKAGE-GENERATORS (version 5)

[David A. Moon <Moon@STONY-BROOK.SCRC.Symbolics.COM>]

    Date: Wed, 30 Nov 88 16:44:47 PST
    From: Jon L White <jonl@lucid.com>

    re: [fix final nits]

    Ok, I'll do it.  I would also like to embellish the sample code for the
    do-mumble-symbols guys to be more nearly workable.  What would you say to 
    the following for DO-SYMBOLS?  [PARSE-BODY is as defined in Guy Steele's 
    "Clarifications" of 6-Dec-85.]

I don't see much advantage to adding more complexity to the macro when we're
trying to show what with-package-iterator does, not how to use parse-body
(which I don't think was ever accepted into Common Lisp anyway).
If you do go down this road, you're just going to have me complaining
that your macro doesn't take an &environment argument, and things of
that ilk.  I'd rather keep it simple.  However, you're writing the writeup,
so do whatever you want.  I only am going to complain about things that
change the definition of Common Lisp, not stylistic details of the examples.

    (defmacro do-symbols ((var &optional (package `*package*) result-form)
			  &body body)
      (multiple-value-bind (body decls docstring) (parse-body body)
	`(with-package-iterator (next-symbol (list ,package)
				 :internal :external :inherited)
	   (let (more? ,var)
	     ,@decls
	     (loop
	       (unless (multiple-value-setq (more? ,var) (next-symbol))
		 (return ,result-form))
	       ,@body)))))