Re: versioning, robustness principle, doctypes etc

Larry Masinter wrote:
> Conformance checks can use a version indicator (doctype for example)  
> to determine which conservative advice should be applied.

Having an in-band version indicator for conformance checking makes the  
following unwritten assumptions:

  * It's appropriate for a person opting to target an older "version"  
not to see more up-to-date advice. (Surely newer advice should be  
assumed to be better informed and, thus, better advice.)

  * If the person running a conformance checker and the person  
producing the markup are different people (or the same person at  
different times), the markup producer should choose the checker target  
"version"--not the person invoking the checker.

Have you compared the model with an in-band spec version number based  
version indicator against the following models?

  * The user of the conformance checker choosing the validation target  
(i.e. out-of-band indication of the wanted profile).

  * The user of an editor that embeds a conformance checker using  
product-specific in-band syntax (consider the Emacs mode line) to  
communicate the validation target, and the target choice may be more  
granular than W3C spec versions (making the in-band indicator non- 

Henri Sivonen

Received on Thursday, 6 August 2009 07:04:30 UTC