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

Re: The <any/> element: bane of security or savior ofversioni

  • From: Thomas Lord <lord@e...>
  • To: Melvin Chin <mc@S...>
  • Date: Sat, 20 Oct 2007 11:41:07 -0700

Re:  The <any/> element: bane of security or savior  ofversioni
Melvin Chin wrote:
> Economically, the need is almost always to convert X-schema
> to Y-schema.

But I'm responding to the scenario another poster
offered earlier up.  That person has a million lines of
legacy code that uses X and the Y to X morphism
is very important to keeping that system running while
making upgrades incrementally.

> If, by definition, a reverse-relation is necessary,
> then that definition almost for sure imposes excessive
> overhead that is not needed in practice.  Furthermore, since
> Y is expected to be an "improved version" of X, it would
> contain extra features which permit elements not recognizable
> in X.  Such reverse translation of Y to X must fail by implication.

Well, no, not really.   It depends entirely on how well designed
X is.

My transform-based approach tells you generally how to
avoid/solve problems like this, but yes, you must *still*
design X with extensions in mind.   It's just that future
formats should be transformable into X extensions, not
that they necessarily have to be represented as X extensions.
That's why it's "too late" for systems already suffering
this problem -- you have to design X with extensibility
in mind in the first place, it's just that designing such an X
is simplified if you think of type conversions rather than
simply sub-types and super-types.


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


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.
First Name
Last Name
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.