DRAFT Issue: HASH-TABLE-PACKAGE-GENERATORS (version 3)

[Kent M Pitman <KMP@STONY-BROOK.SCRC.Symbolics.COM>]

I didn't find your Proposal section to be clear on whether the
body was naturally iterated or whether you had to do your own
iteration. I assumed the latter, but it should be made clearer.
The following example you gave makes things very muddy:

    The following functions prints out every interned symbol:

    (defun print-all-symbols () 
      (with-package-iterator (next-symbol nil)
	(print (next-symbol))))


The problem this caused me is:
 - This doesn't iterate. I assume it just prints one thing and exits.
 - NEXT-SYMBOL is supposed to return a boolean value as its primary
   value. That means this will print a lot of T's, no?

Why not make the first value returned be something useful. I suggest
it should be the hash-key for hash-tables and the symbol for packages.
The second value should be the hash-value or the status, and the last
value should be the valid-p info.