Re: where does this belong?

[prj@po.cwru.edu (Paul Jarc)]

Daniel Pittman <daniel@rimspace.net> wrote:
> I agree with Kai -- the right place for this is the `cl' package,
> because I can't see the difference between this and the `defstruct'
> routine...

Well, the most significant difference is that I didn't know about cl's
defstruct. :)  Now that I do, I see that mine is much smaller:

(defmacro nnmaildir--defstruct (name members)
  "Defines NAME-new, NAME-get-MEMBER, and NAME-set-MEMBER macros."
  (let ((index 0)
        (namesym name)
        member)
    (setq name (symbol-name namesym))
    (eval `(defmacro ,(intern (concat name "-new")) ()
             ,(concat "Creates a new \"" name "\" structure.")
             '(make-vector ,(length members) nil)))
    (mapcar
      (lambda (membersym)
        (setq member (symbol-name membersym))
        (eval `(defmacro ,(intern (concat name "-get-" member)) (,namesym)
                 ,(concat "Returns the \"" member "\" member of a \"" name
                          "\" structure.")
                 (list 'aref ,namesym ,index)))
        (eval `(defmacro ,(intern (concat name "-set-" member))
                 (,namesym ,membersym)
                 ,(concat "Sets the \"" member "\" member of a \"" name
                          "\" structure.")
                 (list 'aset ,namesym ,index ,membersym)))
        (setq index (1+ index)))
      members)
    nil))

But I don't think I understand what the cl defstruct does, exactly.
Can someone point me to an example use?


paul