* Brian Smith <[EMAIL PROTECTED]> [2007-09-14 19:05]: > It seems wrong to me to standardize on a mechanism that isn't > using URIs for identifying entries
The Atom ID *is* a URI. > especially since the idea of permalinks already exists for HTML > representations of entries. Atom Entries need not have a permalink. But they must always have an ID. Permalinks shouldn’t change but sometimes do; Atom IDs MUST be unchanging. We started with the exact same mechanism you suggest: @rel='in-reply-to' links. It didn’t work. We originally said the @href is the Atom ID, but such links are useless to Atom consumers that don’t know `in-reply-to`, just like thr:in-reply-to elements are useless to Atom consumers that don’t know what they mean. So there is no gain from reusing atom:link with overloaded @href. Also, sometimes you have both a permalink and an Atom ID. It would be good to provide both. With a single attribute this is not possible, so you need two. The logical thing to do is put the permalink in @href and the Atom ID in an extension attribute. Then such a link is somewhat useful even to clients that don’t specifically understand `in-reply-to`. Except that doesn’t work. There are two problems: 1. The Atom ID would go in an extension element. But what happens when you have no permalink? After all, atom:link REQUIRES an @href attribute, and with good reason. 2. You have introduced a bad co-constraint. The link extension attribute is only valid on links where @rel has a particular value. You really can’t use atom:link for this. We tried. Regards, -- Aristotle Pagaltzis // <http://plasmasturm.org/>
