Subject: [mmox] LLIDL or schemas?

From: Catherine Pfeffer <[email-masked]>
Date: Tue, 24 Feb 2009 18:20:13 +0100

Jon said:
> I propose that the data structure
> definition language be moved to some XML schema.

Yes, LLIDL makes no sense in the XML world, where there are schemas (or
DTDs) for that.

That's another example of technical compromise needed by this "three
serializations" scheme.

My suggestion would be: "do only one serialization, but do it well"...
 - If XML has an angle bracket tax that is too expensive to pay, especially
on limited capability devices, then let's stick to a binary format only.
 - If XML is the way to go because it's more flexible, human-readable, and
because there's already a bunch of tools for it, then go for it only, but do
it using all the possibilities of the XML technology.

My opinion is that doing an 1:1 transposition of a binary format is just
like automatically translating French into English word per word, it gives
bad (although sometimes really funny) results.

Anyhow, who is asking for a choice between three serializations? Is there a
use case for that?

Don't take it bad, Infinity. I'm just trying to put my engineering knowledge
at the service of realistic and long-term decisions, not to destroy Linden
Lab's vision of the future.

-- 
Cathy

---

From: "Meadhbh Hamrick (Infinity)" <[email-masked]>
Date: Tue, 24 Feb 2009 09:29:55 -0800

hmm.. that's an idea.. we could move the binary and JSON  
serializations to a separate, informational RFC.

honestly... we (Linden) would love to not have to support JSON, but  
the input we got from peeps doing web 2.0-ish stuff is that JSON was  
preferred to XML, which is why it's in the draft.

translating from LLSD to an XML serialization is NOT the equivalent of  
translating from English to French. Human languages tend to have MUCH  
more ambiguity and are MUCH more subject to context.

I would point out that if translating from LLSD to XML is hard, and  
subject to error, then certainly translating from a C data structure  
to XML is also hard and subject to error. both processes consume a  
well defined "atom" of data and produce another well defined "atom" of  
data in a different format.

the use case for the JSON and Binary serializations are in the draft.  
feedback we received from the AWG was that the XML format was too  
encumbering for messages that should be processed quickly. the use  
case for the JSON serialization comes from the people whose product /  
project consumes data from a LLSD data source and uses it in an AJAX  
context.

On Feb 24, 2009, at 9:20 AM, Catherine Pfeffer wrote:

> Yes, LLIDL makes no sense in the XML world, where there are schemas  
> (or DTDs) for that.
>
>  - If XML has an angle bracket tax that is too expensive to pay,  
> especially on limited capability devices, then let's stick to a  
> binary format only.
>  - If XML is the way to go because it's more flexible, human- 
> readable, and because there's already a bunch of tools for it, then  
> go for it only, but do it using all the possibilities of the XML  
> technology.
>
> My opinion is that doing an 1:1 transposition of a binary format is  
> just like automatically translating French into English word per  
> word, it gives bad (although sometimes really funny) results.
>
> Anyhow, who is asking for a choice between three serializations? Is  
> there a use case for that?
>
> Don't take it bad, Infinity. I'm just trying to put my engineering  
> knowledge at the service of realistic and long-term decisions, not  
> to destroy Linden Lab's vision of the future.
>
> -- 
> Cathy
> _______________________________________________
> mmox mailing list
> [email-masked]
> https://www.ietf.org/mailman/listinfo/mmox