Re: annotation-xml and annotation encoding

Le 22 déc. 07 à 15:31, Henri Sivonen a écrit :
>> Applications emitting MathML should, when outputting the encoding  
>> attribute of the annotation or annotation-xml children of the  
>> semantics element, either:
>> 1- use one of the names listed in this spec, if applicable
>> 2- use a mime-type if one exists for the data
>> 3- use a namespace URI if this URI is the namespace URI of the  
>> single root child of an annotation-xml that is being output
>> 4- use an self-decided character string
>>
>> Note that the encoding attribute value of case 4 does not impact  
>> the XML parsing architecture which still needs appropriate xmlns  
>> declarations.
>
> I think that formulation is still problematic.
>
> For annotation-xml, it doesn't explain what value the encoding  
> attribute provides over the namespace of the child element.

It cannot because 1 and 2 are still applicable.
I wonder if 4 and 3 shouldn't be swapped.

> Wouldn't it be better to suggest that legacy generators continue to  
> be allowed to use an encoding attribute on annotation-xml but it  
> must be ignored by consuming apps and the namespace of the child  
> must be used for dispatching instead (and suggest that new  
> generators omit the attribute)?

It is just a commodity feature.
You certainly don't want to ignore an encoding attribute if with 1  
and 2. Or?

> For annotation, point 3 is not applicable. With point 2, it should  
> probably be clarified whether a MIME type is appropriate for  
> fragments.
> It seems to me, that e.g. the value TeX is not used for labeling a  
> full TeX program but a fragment of TeX source that one would use  
> inside a larger TeX program. If one uses similar fragments of  
> another language and the other language has a MIME type for full  
> files, should the MIME type or a self-decided string per point 4 be  
> used for fragments?

This is a never ending story and I do not think it can be decided  
before MathML3 should come out.

For this reason clipboard formats are, in Macs and Windows, in  
several technologies, not the same as mime-types (only Java brings  
them together). But, of course, they are different between these two  
platforms.

Nonetheless, Mime-types are the only standardized encoding names  
hence are the only way towards interoperability. Moreover, mime-types  
are somewhat refinable with the parameters.

Maybe we need more examples?

paul