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Re: PIFLE (was Re: Are PIs useful?)

From: Robert Streich <streich@slb.com>
Date: Thu, 15 May 1997 19:48:20 -0500
Message-Id: <>
To: w3c-sgml-wg@w3.org
At 09:58 AM 5/15/97 -0500, Alex Milowski wrote:
>I simply can't agree on this.  Such information does not belong in the source
>document.  You can easily have ancillary document which describe how to use
>a document or additional semantics.

These are rarely practical due to difficulties in synchronization.

>In many of the systems we are developing in our company, we are creating 
>systems that use *many* document to describe how to accomplish some task or
>present some piece of information.  This allows us to create documents that
>are reusable.
>I can see how this use of processing instructions would be useful but, in my
>opinion, it breaks encapsulation.  In the object-oriented programming world,
>this usually means you are design one class for something that should be
>many.  Applying this rule to the above, you could be trying to describe more
>than one set of information in one document.

From another point of view, encapsulation was broken as soon as the first
piece of markup was inserted into the document. As soon as you put the
first piece of markup in a document, you impose a viewpoint on it thus
limiting the reusability of that chunk of text. The analogy with OO
programming holds true as this is one of the reasons that objects haven't
proven to be as reusable as was originally hoped.

In principle, I agree with you, but I take it a step farther: I don't
think there should be any markup in the text. Structures should only be
associated with text in the same way that we propose presentation is
associated. It just isn't practical at the moment, because of the
difficulty in keeping everything synchronized.

Received on Thursday, 15 May 1997 19:58:52 UTC

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