Re: [SVGMobile12] processing of errors

Hi Charles,

Thanks for your comments archived at 

On 20 mai 2005, at 16:55, Charles McCathieNevile wrote:

> Currently viewers are required to stop processing at the point  
> where a document is, or goes into, error, by 
> SVGMobile12/implnote.html#ErrorProcessing - although I like the  
> fact that the specification requires a highly visible notification  
> of error and hope that is not removed.
> I would like to request that the spec to be altered to suggest that  
> User Agents MAY, after providing such a highlight the error, offer  
> to attempt repair and rendering the document.
> Under the current specification there seem to be two possible  
> sccenarios. The first is that all implementations follow the  
> specification and the pressure on designers to code SVG correctly  
> is irresistable, in which case the question becomes moot.
> In the second case, where there is some real proportion of  
> incorrect content, the first viewer that renders incorrect content  
> places a great deal of pressure on others to follow suit, or  
> provide an unsatisfying user experience and ths lose users.
> The fact that it is explained to the user why they are not being  
> shown what they expect is an important thing. However in many  
> simple cases, a small error in a relatively unimportant document  
> will mean the user suffers "unnecessarily". With a visible warning  
> the user will be told the designer was at fault. This proposed  
> addition is intended to reduce the likelihood that the user blames  
> the browser, and thus reduces the pressure on manufacturers to try  
> and circumvent the specification, increase the likelihood of the  
> designer coding correctly to avoid having a browser point out that  
> they of all designers are incompetent, and reduces the suffering of  
> the user. The intended result is that designers take more  
> responsibility for ensuring their content is conformant, rather  
> than waiting for suffering users to report errors or for  
> manufacturers to ignore the spec in favour of their users.

The working group agrees. The error handling is standardised across  
errors, in particular to require that the user is given a highly  
visible notification that the author has made an error. Obviously  
specifying specifics of wording etc is not practical across the range  
of devices SVG is deployed on, so it is specified as a  
straightforward functional requirement.

The user agent may also note, if it attempts further error recovery  
as a service to the user, that the content on which recovery has been  
attempted should not be relied upon.


Antoine Quint  Fuchsia Design
SVG & Client-side XML Consulting
W3C SVG WG Invited Expert

Received on Thursday, 3 November 2005 14:00:18 UTC