Postel’s Law, RSS, and NetNewsWire
So, you might wonder, why is NetNewsWire’s RSS parser forgiving?
When I started writing NetNewsWire, there were other aggregators already out there that were forgiving.
For example, what happens when an RSS feed has an unencoded ampersand (and is thus not-well-formed XML)? Should NetNewsWire work around the error or not?
(Unencoded ampersands are possibly the most common of errors in RSS feeds.)
At the time I was writing the RSS parser, I believed it should try to work around the error, so it could read feeds that other aggregators could read.
Was that the right or wrong choice? It’s debatable.
But I do like that since Atom is a new format—and because NetNewsWire is already-established software—I have a chance to do it differently.