OASIS Mailing List ArchivesView the OASIS mailing list archive below
or browse/search using MarkMail.


Help: OASIS Mailing Lists Help | MarkMail Help



   Re: An Architecture for Limericks

[ Lists Home | Date Index | Thread Index ]

1/12/2002 8:26:37 AM, Jonathan Robie 
<jonathan.robie@softwareag.com> wrote:

> In general, when designing complex systems, 
> I think it is very helpful to 
> think in terms of declarative, testable 
> architectures.

As usual, Jonathan makes an informed and well-argued 
case for the typed/declarative orientation.  The 
only thing I'd disagree with is whether this is true 
"in general" or mainly in a more limited set of 
situations where one has:

- A well-defined and stable conceptualization of the 
data, as we do for definition of a "limerick".
- Enough of a community of / market for 
interoperating tools and users to make the 
architectural investment worthwhile.
- Some sort of authority to encourage/enforce 
compliance and manage schema evolution.

Perhaps ironically, I see that our great admirer :~) 
Fabian Pascal (echoing much of C. J. Date's recent 
work) makes an argument similar to Jonathan's in a 
critique of the way SQL forces business rules and 
integrity constraints to be validated by stored 
procedures rather than declarative constraint 

Maybe I have the "see worse is better everwhere" 
pattern hard-wired in my brain, but that article 
sure is eerily reminiscent of a lot of discussions 
here! So, I'd leave Jonathan with the same question 
that set Mr. Pascal off into a long rant a few 
months back:  If the logical / declarative / 
architectural "right thing" is such a good GENERAL 
prescription for building information systems, why 
is it so rarely practiced in the Real World? 

My proposed answer is much like my recent reply to 
Al Snell about the upfront design vs incremental 
evolution:  If you have well-known and stable 
requirements and some way to enforce compliance, 
"declarative, testable architectures" designed up 
front will lead to success; if you don't, something 
more like extreme programming / well-formed XML / 
procedural scripting will tend to be more pragmatic.


News | XML in Industry | Calendar | XML Registry
Marketplace | Resources | MyXML.org | Sponsors | Privacy Statement

Copyright 2001 XML.org. This site is hosted by OASIS