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> -----Original Message----- > From: Champion, Mike [mailto:Mike.Champion@S...] > Sent: Sunday, December 30, 2001 1:14 PM > To: xml-dev@l... > Subject: The Two Poles of the XML World (was RE: > W3C's five new XQuery/Xpath2 working drafts - Still missing Updates) > > > Loosely typed, loosely coupled, flow-oriented: "Interesting emergent > properties evolve"; grow complex systems from simple > components and use "gardening" techniques to kill off the bugs and weeds and > rigorously prune unwanted tendrils. XML is just "smart text", putting the > information into XML format simply allows us to "pipe" it between decoupled > processes that use XML tools look for patterns in the messages, insert new > information in the messages, and/or transform the messages to add value for > some downstream process or user. One clarification ... this doesn't mean that one never uses schemas or validation in a loosely coupled system. It may be useful to use a validation step to decide how to route a message, or to determine whether a data cleanup or conversion process has worked properly, and of course this requires some sort of schema or DTD to be defined. The distinction I'm trying to make is that as a general rule, the more one defines a strict datatype "contract" between nodes, the more tightly coupled the overall system becomes, and the system becomes more fragile in the face of change. This fragility is manageable in a small organization, problematic in a large one, and extremely difficult in an application widely distributed over the internet.
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