[XML-DEV Mailing List Archive Home] [By Thread] [By Date] [Recent Entries] [Reply To This Message]

Re: Need a language whiz: An XML Schema "specifies" howdata is

  • From: Rick Jelliffe <rjelliffe@allette.com.au>
  • To: "xml-dev@lists.xml.org" <xml-dev@lists.xml.org>
  • Date: Thu, 4 Jan 2018 13:46:51 +1100

Re:  Need a language whiz: An XML Schema "specifies" howdata is
SGML has the idea of a "document type" which had a "definition", part of which was achieved by the "declarations" i.e. the DTD.  Due to the limitations of any schema language, the document type definition would never be entirely specified using the various declarations available. 

XML Schemas does not have the concept of a document type or language as such: it has groupings of element types of namespaces, at least one of which will be a global declarations suitable for the root element.  For Roger's enquiry, perhaps saying that the schema declares element types in namespaces, and valid documents conform to these types, is a good approach.

(Schematron also does not have an idea of a document type: it has patterns arranged into phases, where the context of some rules may be the document element. A "Pattern" is an ad hoc  "type".)

Regards
Rick

On Thu, Jan 4, 2018 at 3:24 AM, Michael Kay <mike@saxonica.com> wrote:
The essence of the semantics of XSD is that the specification defines a process, variously called "validation" or "assessment", that takes a schema and an instance document as input and produces an assessment outcome as its result.

assess(schema, instance) => outcome

(It's slightly more complicated than that because you can specify other inputs to the assessment, e.g. strict/lax).

The specification does not use any specific term (such as "describes" or "constrains") for the relationship between a schema and the set of instance documents for which assessment has an outcome labeled "valid". You're perfectly welcome to use a term such as "describes" for this relationship if you wish, but it's not a term-of-art in XSD itself; so if you use it, you should say carefully what you mean by it.

Michael Kay
Saxonica


> On 3 Jan 2018, at 14:40, bryan rasmussen <rasmussen.bryan@gmail.com> wrote:
>
> The word choices betray viewpoints of reality -
> stating or specifying how data is to be structured assumes a blank
> canvas and the schema tells you how that canvas may be filled
> constrains assumes that data is a realm of many, perhaps infinite
> possibilities, XML Schema then constrains or limits the possible to
> the manageable.
>
> I am a specifying how data is to be structured man myself.
>
> On Mon, Nov 13, 2017 at 2:13 PM, Costello, Roger L. <costello@mitre.org> wrote:
>> Hi Folks,
>>
>>
>>
>> Which of the following is most accurate and why?
>>
>>
>>
>> An XML Schema specifies how data is to be structured.
>> An XML Schema describes how data is to be structured.
>> An XML Schema states how data is to be structured.
>> An XML Schema constrains the structure of data.
>> An XML Schema structures data.
>> An XML Schema describes data.
>> An XML Schema constrains data.
>> Other (what?)
>>
>>
>>
>> /Roger
>>
>>
>
> _______________________________________________________________________
>
> XML-DEV is a publicly archived, unmoderated list hosted by OASIS
> to support XML implementation and development. To minimize
> spam in the archives, you must subscribe before posting.
>
> [Un]Subscribe/change address: http://www.oasis-open.org/mlmanage/
> Or unsubscribe: xml-dev-unsubscribe@lists.xml.org
> subscribe: xml-dev-subscribe@lists.xml.org
> List archive: http://lists.xml.org/archives/xml-dev/
> List Guidelines: http://www.oasis-open.org/maillists/guidelines.php


_______________________________________________________________________

XML-DEV is a publicly archived, unmoderated list hosted by OASIS
to support XML implementation and development. To minimize
spam in the archives, you must subscribe before posting.

[Un]Subscribe/change address: http://www.oasis-open.org/mlmanage/
Or unsubscribe: xml-dev-unsubscribe@lists.xml.org
subscribe: xml-dev-subscribe@lists.xml.org
List archive: http://lists.xml.org/archives/xml-dev/
List Guidelines: http://www.oasis-open.org/maillists/guidelines.php



[Date Prev] | [Thread Prev] | [Thread Next] | [Date Next] -- [Date Index] | [Thread Index]


PURCHASE STYLUS STUDIO ONLINE TODAY!

Purchasing Stylus Studio from our online shop is Easy, Secure and Value Priced!

Buy Stylus Studio Now

Download The World's Best XML IDE!

Accelerate XML development with our award-winning XML IDE - Download a free trial today!

Don't miss another message! Subscribe to this list today.
Email
First Name
Last Name
Company
Subscribe in XML format
RSS 2.0
Atom 0.3
 

Stylus Studio has published XML-DEV in RSS and ATOM formats, enabling users to easily subcribe to the list from their preferred news reader application.


Stylus Studio Sponsored Links are added links designed to provide related and additional information to the visitors of this website. they were not included by the author in the initial post. To view the content without the Sponsor Links please click here.

Site Map | Privacy Policy | Terms of Use | Trademarks
Free Stylus Studio XML Training:
W3C Member
Stylus Studio® and DataDirect XQuery ™are products from DataDirect Technologies, is a registered trademark of Progress Software Corporation, in the U.S. and other countries. © 2004-2013 All Rights Reserved.