[whatwg] several messages about HTML5

Elliotte Harold elharo at metalab.unc.edu
Wed Feb 21 13:26:46 PST 2007

James Graham wrote:

> Even in cases where the content really is well formed XML the client is 
> entirely the wrong place to enforce validity -- it means that a tiny 
> mistake causes suffering for the person least able to deal with the 
> problem -- the end user. Needless to say this is terrible UI and thus 
> widespread implementation of fatal error handling is, at best, a 
> metastable situation -- as soon as one UA decides they can gain some 
> advantage by including error handling, everyone else has to follow suit. 
> This has happened with many "XML" based feed formats, for example.

That's an interesting argument, and it seems logically sound. However, 
something's wrong with it, though I can't quite place my finger on where 
exactly the mistake lies.

The reason I know that something's wrong with it is that the conclusion 
is not seen in the wild today. Feed readers are in fact swinging away 
from permissive error handling, and are increasingly choosing to simply 
reject malformed feeds, and not bother trying to handle it. Consequently 
far more feeds today are well-formed than was the case a few years ago.

This may be the result of increasing use of better software to generate 
feeds than the homegrown hacks we used a few years ago. WordPress, 
Blogger, and such account for a much larger percentage of the installed 
base than they used to.

There is of course a snowball effect. As more feed readers reject 
ill-formed feeds, blogs have greater incentives to produce well-formed 

The same effect may be possible in the web browser space as well. 
However I think it would have to start with better authoring tools and 
template systems.

Elliotte Rusty Harold  elharo at metalab.unc.edu
Java I/O 2nd Edition Just Published!

More information about the whatwg mailing list