On Monday, May 16, 2005, at 10:59 AM, Tim Bray wrote:
On May 16, 2005, at 6:27 AM, Robert Sayre wrote:On 5/16/05, Tim Bray <[EMAIL PROTECTED]> wrote:The benefit the Web derived from HTML's implicit-but-universally-implemented MustIgnore rule; it introduced enough slack into the system that people could experiment without breaking things.
Don't you think the Feed Validator should flag my example as invalid?
No. I actually thought that what we meant was what the spec said, and that this was the (very reasonable) outcome of our discussion on MustUnderstand. That means that if the IETF wants to extend Atom, we can do it as long as the extensions can be safely ignored. If you want to put something new in that can't be safely ignored, the whole document namespace has to be changed. I thought that the WG had converged on a reasonable and in fact enlightened position and I really would prefer not to go back and repeat the discussion. -Tim
I would think that a warning in that case would be useful that case, since it might be an accidental error--forgetting to prefix an extension element, or misspelling the name of an Atom element. Something along the lines of "Warning: this element is not recognized by the validator as a member of the Atom namespace. It may be from a newer version of the Atom specification than the validator is aware of, or it may be an error."
