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Re: There Are No Metadocuments



At 18:26 10/2/97 -0800, Jon Bosak wrote:
>The problem I'm having with a distinction between behavior and
>appearance is that it just won't stay nailed down.  Most behavior can
>be (and is) described with regard to an appearance, and most
>appearances are the result of some behavior.  Peter has a system that
>uses Java code to perform (among other things) the formatting
>functions that in some other system might be expressed in a
>stylesheet.  Is that behavior or appearance?

If the running of this code is controlled by user interaction at the client
its appearance: if it is action that is forced on the application by
information from the server it is behaviour! (Author defined formatting is
currently being referred to as behaviour: user defined formatting is
currently being referred to as appearance. Both types are required - its the
point of control that defines whether it is a behaviour or not.)
>
>Allow me to generalize that.  For any DSSSL stylesheet that specifies
>that a certain appearance should be associated with a given node in
>the XML tree, I can imagine a Java program that causes exactly the
>same appearance to be associated with the same node.  Suppose that it
>is impossible to tell the difference between the way the document is
>rendered by a DSSSL engine under the control of a stylesheet and the
>way that the same document is rendered by a collection of Java
>programs.  Does the DSSSL stylesheet constitute a specification of
>appearance and the collection of Java programs constitute a
>specification of behavior?

The DSSSL style sheet as sent by the author is a behaviour. The version as
modified by the user, or the overrides issued by the user, is what
constitutes a change of appearance. The terms appearance and behaviour are
misleading, like addresses/locators/explainers.... They say what the result
is, not what you need to get there. What we need is something like local
control parameters and remote control parameters to distinguish where
control actually lies.
----
Martin Bryan, The SGML Centre, Churchdown, Glos. GL3 2PU, UK 
Phone/Fax: +44 1452 714029   WWW home page: http://www.u-net.com/~sgml/