Re: Canonical Way to Mask SETF?

Robert Uhl <eadmund42@xxxxxxxxxxxxxxx> writes:

> I'm playing with a menu system, and would like to be able to write the
> following:
>
> (menu-item menu) -> item
> (setf (menu-item menu) item)
>
> I figured that something like this would do the trick:
>
> (defun menu-item (menu)
> (getf menu :title))
>
> (defsetf menu-title (menu) (title)
> `(setf (getf ,menu :title) ,title))
>
> But of course it doesn't work. Any advice on how this needs to be
> written?

Maybe you want to call the defun menu-TITLE, not menu-ITEM?
Or you want to call the setf function menu-ITEM, not menu-TITLE?

Otherwise I don't see why it shouldn't work.

> Unfortunately there aren't too many online references which deal with
> DEFSETF--at least none that I've found.

It's not supposed to be hard. It's like you did it, just with spelling
done right.
.

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