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   Re: [xml-dev] ASN.1 is an XML Schema Language (Fix those lists!)andBinar

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Robin Berjon wrote:
> Alaric B Snell wrote:
>> Robin Berjon wrote:
>>> If all you have is an ASN.1 schema, and you're on the receiving side, 
>>> you don't know what you're going to get. If it's an ER you don't know 
>>> about you won't read it. That just won't happen if you're using XML. 
>>> You can chose to consider this unimportant, but a lot of us XML folks 
>>> think it is a core asset.
>> Heheh, any XML folk who thinks that this is an asset of XML haven't read:
>> http://www.w3.org/TR/REC-xml#charencoding
>> "processors are, of course, not required to support all 
>> IANA-registered encodings"
> There are several levels of concreteness, and they will vary according 
> to who you talk to. To some endianness is of high importance, while 
> others will tell you that it doesn't matter at the level at which they 
> are working. XML hits the concrete level when it reaches Unicode, 
> anything below that being pretty much someone else's problem. I guess 
> that's part of what makes it a textual format.

I think the level of concreteness you were referring to was that 
required for interoperability. Somebody somewhere along the line seemed 
to incorrectly think that a standards compliant XML parser could parse 
any standards compliant XML document. However, XML is not that 
interoperable; valid documents may be rejected by the parser because it 
just doesn't know the character set involved.

"The ASN.1 equivalent of a simple XML parser in terms of universality 
would have to properly decode (and likely handle negotiation for) BER, 
PER, CER, DER, XER, and probably LWER, OER, and SER. That's a bit of a 
behemoth to implement!"

The ASN.1 'equivelant' of a normal XML parser would just need to support 
BER, which is the current conventional "minimal" encoding. An ASN.1 
toolkit that supported "BER, PER, CER, DER, XER, and probably LWER, OER, 
and SER" would be more closely related to an XML parser that supported 
US-ASCII, UTF-8, UTF-7, UTF-16, EBCDIC, ISO-8859-[1..15], Shift-JIS, 
Baudot, etc...

> That being said, I'd have been happier with just UTF-8 and UTF-16, but 
> I'm nevertheless happy with what we have now.

So you *aren't* one of these people who thinks that a single concrete 
syntax (for interoperability reasons) is important, then? :-)



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