Change Proposal

Document conformance has to be stable over the time

Summary

Currently the document conformance relies on external registries which are not versioned -- they can add or remove any value at any time. This means that validity of frozen documents might change over the time. In some situations this is unacceptable as document conformance is considered to be one of acceptance criterias for web sites delivered to customer. If the document conformance can change overnight web authors are not secured from their work being questioned after external registry is changed in the backwards incompatible way. This proposal releases several conformance criteria in order to create more stable and predicteble environment for HTML code validation

Rationale

The current spec can make existing conforming pages non-conforming overnight. Web environment should be stable and predictable and change in external registry shouldn't retroactively change conformance of HTML5 document.

Details

Change (in section 4.2.5.2): "Conformance checkers must use the information given on the WHATWG Wiki MetaExtensions page to establish if a value is allowed or not: values defined in this specification or marked as "proposed" or "ratified" must be accepted, whereas values marked as "discontinued" or not listed in either this specification or on the aforementioned page must be rejected as invalid. Conformance checkers may cache this information (e.g. for performance reasons or to avoid the use of unreliable network connectivity).

When an author uses a new metadata name not defined by either this specification or the Wiki page, conformance checkers should offer to add the value to the Wiki, with the details described above, with the "proposed" status."

to

"Conformance checkers *may* use the information given on the WHATWG Wiki MetaExtensions page to establish if a value is allowed or not: values defined in this specification or marked as "proposed" or "ratified" must be accepted, whereas values marked as "discontinued" or not listed in either this specification or on the aforementioned page must be *reported* as invalid. Conformance checkers may cache this information (e.g. for performance reasons or to avoid the use of unreliable network connectivity).

When an author uses a new metadata name not defined by either this specification or the Wiki page, conformance checkers *may* offer to add the value to the Wiki, with the details described above, with the "proposed" status."

Analogic edit has to be done in sections "4.2.5.4 Other pragma directives" and "4.12.4.14 Other link types".

Impact

Positive Effects

• More stable environment for document conformance is created

Negative Effects

• Error in registry which is later corrected will not mark document as non-conforming

Conformance Classes Changes

None

Risks

None

References

• List references