My own thought here is that we have three options:
Define standard behavior that applies to all cases, no
exceptions.
Say that the behavior is implementation dependent,
possibly giving an example of a desired behavior that may be implemented.
Provide a standard behavior and a way to designate
exceptions to that standard behavior.
For this particular case I don’t think #3 would be too
hard and so that would seem to be a good way to go.
I am uncomfortable with the option that is being proposed which
I take as defining standard behavior, but allowing exceptions. The reason
I am uncomfortable with this is that it requires that someone who wants to
define a new specialization that requires exceptions provide both the
specialized elements and behavior. We have a standard way to provide the
specialized elements. We do not have a standard way to provide the specialized
behavior. Without a standard way to provide the specialized behavior, someone
will need to reimplement the specialized behavior for different output
processing implementations. That will be extra work and seems likely to result
in different results as documents are moved from site to site and
implementation to implementation. We should avoid that if we can.
I could live with option #1 (no exceptions). That puts
the burden on the author to use the “right” map elements when the
behavior they want isn’t the standard behavior.
I could live with option #2 (no standard). That is
what we do for most output processing today.
And as I said, I think option #3 is the best approach.
I think all we need is either:
a)
a new attribute similar to domain on the root element
of a map that accepts a space separated list of topicref specializations whose
behavior should not be overridden when they are referenced using a different element
from a higher level map, or
b)
a new attribute similar to class on topicref and
topicref specializations that indicates that this element’s behavior
should not be overridden when referenced from a higher level map.
In either case, like domain or class, the new attribute would
usually appear with its default value in a DTD or schema and not in the
instance.
And, if we want to, rather than using a simple list or a
single attribute value, we might define a keyword or grouping syntax for the
values so that we could use the same attributes for other similar purposes in
the future should the need arise. Some possible approaches:
Simple
list on the root element: norefoverride=”element1 element2 …
elementn”
Single
valued attribute on the topicref element or specialization: refoverride=”no”
Grouping syntax on the root element:
processing_exceptions=”norefoverride(element1
element2 … elementn) somenewoption(somenewvalues)”
Keyword
list on any element: processing_exceptions=”norefoverride somenewoption
someothernewoption”
-Jeff
From: Michael
Priestley [mailto:]
Sent: Monday, September 10, 2007
12:06 PM
To: Grosso, Paul
Cc:
Subject: RE: [dita] Issue 12055
Map referencing behaviors
I think the wording needs some clarification - I don't
think what you're reacting to is actually Robert's intent.
Robert,
I'm going to try to paraphrase here:
If
someone specializes a map to create a new map-referencing element, they can
define specialized processing for that element if they want. Applications that
are not customized or extended to provide special handling for the specialized
element should instead treat the specialized element according to its ancestry
(ie, according to whatever behavior is provided in the spec for that element).
I
don't think Robert is saying more than the above, and that's true of all
specializations. He's just pointing out that the behavior defined in the spec can
be overridden by someone providing specialized elements and behavior.
Why
is it worth calling out at all then? I think because there are some behaviors
that we consider architectural (eg conref, the class attribute...) that need to
be consistent across specializations because they are designed to provide
interoperability across specializations; there are other behaviors that are
implementation-specific, in which the behaviors we provide are defaults that
can be overridden, rather than normative for the class of all possible DITA
document types. I think map-referencing behaviors fall in the latter class, and
that's what Robert is trying to say.
Robert,
correct me if I'm wrong. Paul, does that re-interpretation address your
concerns?
Michael
Priestley
Lead IBM DITA Architect
http://dita.xml.org/blog/25
"Grosso, Paul"
<>
09/10/2007 11:27 AM
To
<>
cc
Subject
RE: [dita] Issue 12055 Map referencing
behaviors
Robert,
If I understand correctly, you are suggesting that
different
specializations can do different things based only
on some
writeup in the standard.
Jeff and I have said that is the one choice we
find unacceptable.
Either there needs to be some machine-readable way
to determine
behavior (e.g., encode it in the DTD/XSDs), or all
behavior must
be consistent. Having to hardwire
potentially conflictly behavior
into an implementation for each specialization is
not a good option.
Jeff and I will try to discuss this some more
before tomorrow's
meeting, but I wanted to respond as soon as
possible.
paul
>
