Re: XML InfoSet and property value preservation

Lisa Dusseault wrote:
>> I don't want to be lax. We should either document what we have today 
>> (if we want to advance RFC2518), or document what we tjink would be 
>> good (staying at proposed). Throwing in things like PIs, but keeping 
>> out *essential* things like prefixes doesn't make any sense to me, 
>> though.
> 
> Great; so what's a principled basis on which to make this decision?  I 
> can see one extreme option, plus an "exclusionary" choice and an 
> "inclusionary" choice based on what we know implementations do today.  
> This isn't full text for each point but just illustrative:

I'm tempted to say "common sense". That PIs and comments do not 
necessarily round-trip should be quite clear.

> Extreme option:  All InfoSet items MUST be preserved.  [This clearly has 
> the disadvantage of making existing implementations change their code to 
> comply, but has the advantage of simplicity and enforcing the greatest 
> consistency between servers.]

Looking at what exactly is in (see 
<http://www.w3.org/TR/2004/REC-xml-infoset-20040204/#infoitem>), I find 
that completely unreasonable.

> Exclusionary option: All InfoSet items MUST be preserved, except for the 
> ones we know aren't preserved in some server implementations (comments 
> and prefixes... )  [This encourages nearly as great consistency as the 
> extreme option.]
> Inclusionary option: Of the InfoSet items, only the ones we know client 
> implementations really need (text, element, attribute name and value...) 
> MUST be preserved.  [The difference between this one and exclusionary 
> option covers InfoSet items like Processing Instructions.  ]

I think the latter option has the advantage that it's shorter to write 
down, and easier to understand.

> Has anybody considered this issue besides myself and Julian?  Does 
> anybody with an implementation wish to speak up and argue why it might 
> be important to preserve or useful to discard various pieces of the 
> InfoSet in property values?

Best regards, Julian

Received on Tuesday, 15 November 2005 19:03:13 UTC