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Re: A "processing model" proposal

From: Erik Bruchez <ebruchez@orbeon.com>
Date: Fri, 17 Feb 2006 00:34:39 +0100
Message-ID: <43F50C0F.1060709@orbeon.com>
To: public-xml-processing-model-wg@w3.org

Richard Tobin wrote:

 >> | I also want a single output to be
 >> | connectable to multiple steps' inputs, but we could have (conceptually
 >> | at least) a "tee" component that produces multiple copies of its
 >> | input.
 >>
 >> I think that's fine as long as they're labeled. I think we should make
 >> infosets immutable. That is, a process can transform A to produce B,
 >> but A still exists and hasn't been changed.
 >
 > Conceptually, yes.  If two steps have the same infoset as input, then
 > one step shouldn't be able to change what the other one sees.  In terms
 > of APIs, an implementation might want to make infosets mutable, in which
 > case it must provide separate copies.  Sending one infoset to two steps
 > also has implications for streaming, of course.

Yes. In XPL, we have decided to make infosets immutable:

   http://www.w3.org/Submission/xpl/#output-invariance

This makes sense especially if you come from a "functional" background. 
I don't know if there is a real point of making them mutable.

-Erik
Received on Thursday, 16 February 2006 23:37:08 GMT

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