RE: [dita] How much flexibility do specializers have to make exceptions to behaviors that are outlined in the DITA standard?

["Ogden, Jeff" <jogden@ptc.com>]

Michael wrote:

> This ground feels familiar - here's the examples we were discussing last

> year when we left off - they are examples of cases where it could be

> appropriate to override default behaviors for conref, metadata

> inheritance, etc. So you'll need to explain how my concerns don't

> apply in the context of these examples.
>
> http://lists.oasis-open.org/archives/dita/200710/msg00013.html

 

JO:  . . . here are some examples of overrides that I don’t think we should allow:

 

JO: Allowing a reference of the form “#elementid” to reference sub-topic content.
MP: if someone's using a CMS and assigning GUIDs to every element, they may actually have one unique identifier per element, rather than per topic+element.

 

JO: Using a single GUID to reference DITA sub-topic content should not be allowed. No exceptions.

 

MP: That said, I see your point - it would be preferable for the tool to externalize the reference as properly formed DITA, even if it is internally managed differently. I can easily see the syntax of the href and conref attributes, along with the domains and class attributes, as being immutable. That said, if someone wants to override what they do with that syntax (for example, fetching the linktext for the subelement from its parent topic), I would think that's reasonable.

 

JO: See my comment below that starts out “I just think that if we make everything overrideable …”.

JO: Allowing specializations to give new meanings to or ignore the meanings of existing attribute/value pairs (scope=”external”).
MP: maybe there's a difference here between "meaning" and "behavior". For example, current behavior for scope="external" might be to open up a new browser window - but in a particular delivery context they might actually want to popup an intermediate window that says "you're leaving the website and everything after this is unwarrantied" or something. Not changing the meaning, but definitely changing the behavior.

JO: The specific example given here seems fine to me.  But take a related example, that uses scope=”peer”. Today scope=”peer” is used to say that the referenced item isn’t currently available for processing, but it is part of the same document set.  I think this definition should be true in all cases.  What one does with items that are part of the “same document set” could be customized, but not the fact that the item is considered part of the same document set.

JO: Allowing specializations to ignore @lockmeta.
MP: I can imagine a draft review process that pulled in "author" info from the target topics, even though lockmeta was set, because they wanted to use a single map for both review and for final publication, and they only wanted the author info for review... So in this case, I am imagining a process that would ignore lockmeta to do a particular metadata fetch based on business need rather than specialization.

JO: Wouldn’t it be better to honor lockmeta and always push or not push the metadata values from the map into the topic, and then using an output appearance customization render or not render the “author” info as appropriate for review or for final publication?

JO: Or wouldn’t it be better to define lockmeta as an attribute that can inherit its value and then add lockmeta to the map root element, topicref, topichead, and topicgroup so that someone that wants this behavior can change the value for an entire document or portions of a document as desired?

JO: Or to define a way to set, change, or delete attribute values using conditional processing and ditaval?

JO: Allowing properties that normally cascade from a map to a topic to not cascade depending on the specializations in use.
MP: if a group was doing extensive customization in a map, and was tracking authorship of the map at a chapter level, I can imagine overriding the normal cascade of metadata from map to topic to stop author from cascading and implying authorship of the actual topics rather than of the referencing map sections.  Again, a customization not based on specialization, but still definitely an override of default behavior.

 

JO: Doesn’t this indicate that author information is being used for different somewhat ambiguous purposes (map author vs. topic author) and that to remove the ambiguity one should really create a specialization that includes a second set of map-author information?  And because this would be a specialization, it would be OK to define new rules for inheritance/cascading or even to allow the new element(s) to cascade, but then later be ignored during output (appearance) processing?  And, if this is a common enough need, we could consider adding map-author information to the standard definition for map.

 

MP: I can definitely see the point of preserving the syntax and meaning of our core attributes - but not sure how much of subsequent behavior we can really standardize beyond "don't be an idiot".  For example, we have a "<b>" element that should be rendered as bold - but if someone has a compelling reason to override that (like bold text has been reserved for warnings only), then I think adopters should have the freedom to define their own output processing, even when it deviates from what's in the spec.

 

JO: How one shows something as “bold” is an output appearance issue and so I think a customization along these lines would be fine.

 

> http://lists.oasis-open.org/archives/dita/200710/msg00051.html

 

MP: I was thinking of addressing as "what the syntax means" - for example topicid/elementid - we wouldn't want that to be overridden by processing, it's not even clear to me what overriding that would mean. But I buy that processing for addresses should not ignore or misinterpret the actual information in the address. That said, all the processes that do something with the info at that address should be overrideable - like shortdesc pulling, link creation, etc. etc.

 

JO: I just think that if we make everything overrideable that there is nothing that users or vendors can count on as they exchange DITA documents and specializations. Getting back to what started this discussion long ago, I think it would be better if we can identify behaviors for which it is important to allow for different non-appearance customizations, that we define standard ways to request the behavior that is desired using standard DITA syntax. This might just be a new attribute on elements that has as a default value that could be specified by the specialization author that is a list of the common behaviors. If the default is to pull shrotdesc, create links, and to cascade, then we might have @defaultprocessing=”noshortdescpulling nolinkcreation nocascade …”.  This would make some of the behaviors customizable as well as standard. It would make it much easier for users to exchange documents and specializations without having to develop many system dependent customizations to go with them. We could even make the list of tokens that can be included in the list open ended. That would allow new customizations to be implemented once for a particular system and then shared by different specializations after that.

 

JO:  And if we are not willing to build something into the standard that allows specializers to call for different non-appearance behaviors, my preference is that we define these non-appearance behaviors to be required, so that authors and specializers that follow the standard can exchange documents and specializations with confidence and without having to do a lot of additional customization work to get the non-appearance behaviors that they want.  While I think this is the right approach, the rules that I proposed fall well short of this in that they only call for these non-appearance behaviors to be required on the base topic or map document types.

 

MP: As another conref example: we say you can generalize on the fly where necessary/appropriate - I can imagine someone overriding the generalization to, for example, generate titles for specialized sections that are being generalized during conref. Is that ok?

 

JO: I’d think it would be fine to allow the generation of titles for specialized sections that don’t have them (or even which do have them), but I’d think this would be an output appearance customization and not something that was part of conref processing.

 

JO: But even if you really want this to be part of conref processing I think it might be OK as long as the generated content is valid DITA XML for the context in which it is being used.  I am a little uneasy about this because even if this is allowed it would not be the default behavior and so users can’t count on the behavior being available or easily available as they move their documents from system to system.

 

MP: Are there other conref overrides that wouldn't be ok, for example overriding the process to allow conref across specializations without generalization at all?

 

JO: I think there needs to be enough validation according to the standard and with no exceptions so that we know that the conref content either is or that it could be valid at the point where it is being included.

 

> http://lists.oasis-open.org/archives/dita/200710/msg00050.html

MP: Couldn't an implementer decide that they want to limit reuse in their organization to content coming from specific directories? For example, check the conref path to ensure that it starts with "/reuse/"?

Answer from the original e-mail exchange: JO: I don’t see a problem with this as long as the implementer is being more restrictive than what is required by the standard.  The standard says that conref values are URIs that reference DITA content with a number of checks to make sure the content being referenced is legal or is likely to be legal in the new context.  Limiting the references to a particular path isn’t violating that. The conref values that start with /reuse/ will always be valid URI and with a bit of luck the thing being referenced will be DITA content that is legal in the current content. An implementation will not have to do anything special to make the required checks. You can’t expect other implementations to impose the same limitations automatically, but that is OK.

 

 

---

From: Michael Priestley [mailto:mpriestl@ca.ibm.com]
Sent: Sunday, January 06, 2008 4:52 PM
To: Ogden, Jeff
Cc: dita@lists.oasis-open.org
Subject: RE: [dita] How much flexibility do specializers have to make exceptions to behaviors that are outlined in the DITA standard?

 

This ground feels familiar - here's the examples we were discussing last year when we left off - they are examples of cases where it could be appropriate to override default behaviors for conref, metadata inheritance, etc. So you'll need to explain how my concerns don't apply in the context of these examples.

http://lists.oasis-open.org/archives/dita/200710/msg00013.html
http://lists.oasis-open.org/archives/dita/200710/msg00051.html
http://lists.oasis-open.org/archives/dita/200710/msg00050.html

Michael Priestley
Lead IBM DITA Architect
mpriestl@ca.ibm.com
http://dita.xml.org/blog/25

"Ogden, Jeff" <jogden@ptc.com>

01/04/2008 06:12 PM

To	Michael Priestley/Toronto/IBM@IBMCA
cc	<dita@lists.oasis-open.org>
Subject	RE: [dita] How much flexibility do specializers have to make exceptions to behaviors that are outlined in the DITA standard?

 

Michael,
 
I think you are worried about something that won’t really apply.
 
The DITA specifications are mostly silent about issues related to output appearance (as they should be).   And when the specification is silent no requirement is imposed.  If there are areas where the specification does talk about output appearance we should either remove them from the standard or make sure there is appropriate wording accompany each one that makes it clear that they are examples and not requirements.
 
But there are other areas that aren’t primarily about output appearance. For example: inheritance or cascading of properties, metadata, and attribute values; the syntax and interpretation of href values; key reference processing; or conref processing. Here I think the specification does (and should) impose requirements.  I think most of these non-appearance requirements should be imposed on all DITA doctypes including specializations, but to make progress because you and others don‘t agree, I backed off on this and just imposed the non-appearance requirements on generic topics and maps.
 
It is an open question if we should impose these non-appearance requirements on the standard DITA specializations (concept, task, reference, glossary, and soon the learning and training specializations and machine industry specializations). I sort of think we should, but I realize I am fighting an up hill battle on this.  I think that because these are standard specializations, that if we want to allow exceptions from the base DITA non-appearance behavior, that we should do that explicitly in the DITA standard (and if we put the exceptions into the standard they aren’t really exceptions anymore).
 
For specializations that aren’t part of the standard we would not impose either appearance or non-appearance requirements. Here we would only impose the “markup/syntax” requirements.
 
In our discussions we’ve been talking about “markup/syntax” and “processing behaviors”.  Perhaps we need three categories:
Markup/syntax;
Non-appearance related processing behaviors; and
Appearance related processing behaviors.
 
While the three categories may be right, I don’t much like the specific terminology and would welcome better suggestions.
 
    -Jeff
 

 

---

From: Michael Priestley [mailto:mpriestl@ca.ibm.com]
Sent: Friday, January 04, 2008 4:58 PM
To: Ogden, Jeff
Cc: dita@lists.oasis-open.org
Subject: Re: [dita] How much flexibility do specializers have to make exceptions to behaviors that are outlined in the DITA standard?
 

Hi Jeff,

I'm uncomfortable with the first resolution below: "For the base topic and map types both the “markup/syntax” and “processing behaviors” described in the DITA specifications are required."  Specifically, I think the processing behaviors should remain explicitly overrideable - maybe "required to be provided as default behaviors"?

I believe there are cases where processing behaviors even for generic topics and maps could legitimately be overridden by implementors. Otherwise we are claiming that, for example, no one can generate links from maps except in the way we specify, or change the way something is formatted... There were a few examples I came up with before the holidays, I'll try to find them in the archives.

In the meantime, the architectural spec does have an explicit statement on processing customization: http://docs.oasis-open.org/dita/v1.1/OS/archspec/customize.html

"When you just need a difference in output, you can use DITA customization to override the default output without affecting portability or interchange, and without involving specialization.

For example, if your readers are mostly experienced users, you could concentrate on creating many summary tables, and maximizing retrievability; or if you needed to create a brand presence, you could customize the transforms to apply appropriate fonts and indent style, and include some standard graphics and copyright links.

Use customization when you need new output, with no change to the underlying semantics (you aren’t saying anything new or meaningful about the content, only its display)."

Michael Priestley
Lead IBM DITA Architect
mpriestl@ca.ibm.com
http://dita.xml.org/blog/25

"Ogden, Jeff" <jogden@ptc.com>

01/02/2008 03:30 PM

 

To	<dita@lists.oasis-open.org>
cc
Subject	Re: [dita] How much flexibility do specializers have to make exceptions to behaviors that are outlined in the DITA standard?

 

 

There are four long standing items toward the end of the DITA TC agenda:
1.        How much flexibility do specializers have to make exceptions to behaviors that are outlined in the DITA standard? (MUST, SHOULD, MAY discussion)
  http://lists.oasis-open.org/archives/dita/200710/msg00025.html

2.        What does it mean when we say that an implementation supports the DITA standard? Is the entire standard required or are some parts optional?
3.        Is the scope of DITA 1.2 as it is shaping up too large? Is the DITA specification becoming too complex?
4.        Is the approach outlined in the proposed DITA 1.2 documentation TOC a good approach?
 http://wiki.oasis-open.org/dita/Draft_1.2_TOC
We had some good e-mail exchanges on the first item back in late October.  The e-mail discussion is included below.  I don’t think that that discussion lead to a consensus or any action items.
 
I’d like to finish up the discussion on the first item, so we can start to work our way through the next three items. I propose that anyone who wishes send any last thoughts on this topic to the DITA TC e-mail list between now and next Monday, that we have a brief discussion during next week’s DITA TC call to see where we stand, and as part of that discussion see if we agree to the following as a resolution of this issue:
 
1.        For the base topic and map types both the “markup/syntax” and “processing behaviors” described in the DITA specifications are required.
 
2.        For specializations the “markup/syntax" described in the DITA specifications is required unless explicitly stated otherwise.
 
3.       For specializations the "processing behaviors" described in the DITA specifications are not required, but are strongly encouraged default behaviors unless explicitly stated otherwise. Here “strongly encouraged” means that there may be valid reasons in particular circumstances to implement exceptions to the described default behavior, but the full implications of such exceptions must be understood and carefully weighed before choosing to implement behaviors that differ from the default behaviors described in the DITA specifications.
 
4.        For user defined specializations specific implementations will usually require possibly substantial additional effort on the user’s part to implement exceptions to the default output processing behaviors as described in the DITA specifications. Such implementations are considered fully compliant with the DITA specifications.
 
5.        Using the general guidelines outlined above the specification editors will review and update all of the DITA specifications to ensure they are clear about what MUST, SHOULD, or MAY (see RFC 2119) be done with respect to both the DITA document types that are officially part of the standard (topic, map, concept, glossary, reference, task, bookmap, learning/training specializations, and machine industry specializations) and for user defined specializations that aren’t a formal part of the standard.
 
6.        Members of the DITA TC are encouraged to send suggestions to the specification editors about specific items in the specifications that should have explicitly stated exceptions to the general rules given above.  Suggested exceptions can call for either stricter or loser requirements.  Any differences of opinion about exceptions will be resolved as part of the review and approval process for the DITA 1.2 specifications.
 
 -Jeff
 
 
From: Ogden, Jeff [mailto:jogden@ptc.com]
Sent: Monday, October 15, 2007 5:39 PM
To: dita@lists.oasis-open.org
Subject: [dita] How much flexibility do specializers have to make exceptions to behaviors that are outlined in the DITA standard?
 
We’ve had some e-mail discussions about “How much flexibility specializers have to make exceptions to behaviors that are outlined in the DITA standard”. But those discussions have been fairly quiet for 10 days or so.  We had some good discussion of this during the last DITA TC meeting.  During that discussion we agreed to move the discussion back to the DITA TC e-mail list.  
 
So this note is my attempt to get the e-mail discussion restarted.
 
I don’t think we want to talk about this issue during tomorrow’s DITA TC call, but if we can get some good discussion going on the e-mail list we may be ready to talk about it during next week’s call.
 
I think Gershon’s draft meeting minutes provide a pretty good summary of the discussion, so far. From the draft 9 October 2007 meeting minutes:
 
>          4) How much flexibility do specializers have to make exceptions to
>            behaviors that are outlined in the DITA standard?
>
>                JO: We had good discussions. MP has a more liberal approach,
>                whereas I feel we should not permit as much flexibility.
>
>                MP: I'm drawing the line between syntax and behavior. Syntax
>                must be preserved. Everything beyond there is pretty contextual.
>
>                JE: There are edge cases where we've had to deviate from the
>                standard in order to achieve the specialization we needed.
>                Though these are minor deviations that could be easily
>                transformed back into standard DITA.
>
>                Discussion...
>
>                MP: If someone wants to override the stated default behavior
>                (for some good reason), I don't think we should call that going
>                against the DITA spec.
>
>                Discussion...
>
>                Don requested we move this discussion to the email list.
>
>                Yet further discussion...
>
>                Don asked us to take items 3 and 4 off into 2 discussions next
>                week. In the meantime, continue discussions on-list.
 
Much of the discussion so far has been between Michael and me.  I’d like to see if we can get some others to express their views on this issue.  If most people don’t care or if most people agree with Michael that specializers can do pretty much anything they want, we may not need a lot more discussion.  If this position makes some people uneasy, then we need to find that out and we will need to continue the discussion to figure out how and where to draw some lines.
 
I believe that there is agreement that specializers have a lot of control and can change many things related to output processing behaviors of their specializations. I think there is also agreement that we need to review the DITA specifications to make sure they are clear about what MUST, SHOULD, or MAY be done with respect to both the basic DITA document types that are officially part of the standard (topic, map, concept, glossary, reference, task, and bookmap) and for user defined specializations that aren’t a formal part of the standard. I am a little less sure, but I think there is agreement that we want to add some sort of conformance statement to the DITA specifications.
 
The question that is up for discussion is, are specializers free to do anything they want or are there some things that the DITA Standard makes out of bounds even for user defined specializations that aren’t part of the official DITA standard?
 
From my point of view, I’d like to see some limits on what specializers can do in terms of referencing behaviors (what legal DITA URI’s can look like and what they mean), and when there are interactions such as property cascading behavior between one document and another (from a map to a topic or from a map to a map to a topic).  I want to increase the likelihood that DITA users can share their documents, including specialized documents, with others or move the documents into new processing environments and still get good results.  I want to reduce the amount of reimplementation users have to do when they share their documents or move into new processing environments.
 
Paul Grosso described this in terms of the distinction that is made in XSLT between transformations and styling. Styling would be very open and specializers could do pretty much whatever they want.  Transformations (explicit or implied) would be more tightly defined by the DITA Standard and specializers would have less flexibility (but still some flexibility).  Paul, feel free to restate this if what I wrote here isn’t quite right.
 
I’ll shut up now. Please let us know what you think.
 
  -Jeff
 
 
 
From: Deborah_Pickett@moldflow.com [mailto:Deborah_Pickett@moldflow.com]
Sent: Tuesday, October 16, 2007 11:56 PM
To: Ogden, Jeff
Cc: dita@lists.oasis-open.org
Subject: Re: [dita] How much flexibility do specializers have to make exceptions to behaviors that are outlined in the DITA standard?

"Ogden, Jeff" <jogden@ptc.com> wrote on 16/10/2007 07:39:06 AM:
> The question that is up for discussion is, are specializers free to
> do anything they want or are there some things that the DITA
> Standard makes out of bounds even for user defined specializations
> that aren’t part of the official DITA standard?

I prefer for the standard to make no promises, and let specializers take as much rope as they need.

> From my point of view, I’d like to see some limits on what
> specializers can do in terms of referencing behaviors (what legal
> DITA URI’s can look like and what they mean),

Interesting that you bring up URIs.  Inevitably some specialization is going to come along that wants to link to somewhere in a way that isn't covered by existing hrefs.  We don't have a standard way of making new href-like attributes, and to cater to those specializations we need to.  Or do we: is this what data/@href is for?

And because that made me think of xlink, it reminds me that something we have also not discussed for an awfully long time is namespaces.  Are DITA specializers allowed to add namespaced attributes?

> I want to increase the likelihood that DITA users can
> share their documents, including specialized documents, with others
> or move the documents into new processing environments and still get
> good results.  I want to reduce the amount of reimplementation users
> have to do when they share their documents or move into new
> processing environments.

This is a little tangential, but depending on how we approach a solution, it might not be.

I suppose that a common scenario is that I have a document that contains a specialization, but for $transform I don't have any processing to handle that specialization, so I get fallback behaviour.

Sometimes fallback behaviour is fine.  The UI domain, for instance, is hardly groundbreaking, and falling back to <ph> is not going to hurt.

Sometimes fallback behaviour is ugly.  The Utilities domain's <imagemap> element doesn't really work if rendered as a plain <fig>: you end up seeing the coordinates as plain text.  (I suppose the real culprit here is the <shape> element rather than its ancestor imagemap, and that if it were omitted you'd get something at least presentable.)

How can the processor know when fallback behaviour is acceptable?  Is there some way for a <shape> to say to the processing for its base topic/keyword, "skip me" (or "die")?  (Obviously the answer today is "no, there isn't", so really my question is "is this something we want?".)

--
Deborah Pickett
Information Architect, Moldflow Corporation, Melbourne
Deborah_Pickett@moldflow.com
 
 
From: Michael Priestley [mailto:mpriestl@ca.ibm.com]
Sent: Thursday, October 25, 2007 3:21 PM
To: Eliot Kimber
Cc: dita
Subject: Re: [dita] How much flexibility do specializers have to make exceptions to behaviors that are outlined in the DITA standard?

Hi Eliot,

Re:
> All addressing of DITA-governed content by DITA-governed content. That is,
> you cannot, within a specialization, change the rules for resolving hrefs
> (or any other DITA-defined addressing mechanism)) to DITA-based content.

Couldn't the implementer choose to create hoverhelp for a link to APItopics by summarizing the syntax, rather than always pulling the shortdesc? Agreed the syntax should be consistent, but why limit what we do with that syntax?

> Conref. You cannot change the constraints or effective result that conref produces.

Couldn't an implementer decide that they want to limit reuse in their organization to content coming from specific directories? For example, check the conref path to ensure that it starts with "/reuse/"?

It seems to me that one of the advantages of having conref as an explicit process rather than something that happens as part of parsing (as with entities or XIncludes) is that you can, as an implementer, choose to enhance or restrict the processing according to your local requirements.

Michael Priestley
Lead IBM DITA Architect
mpriestl@ca.ibm.com
http://dita.xml.org/blog/25
 
 
-----Original Message-----
From: Eliot Kimber [mailto:ekimber@reallysi.com]
Sent: Thursday, October 25, 2007 3:10 PM
To: dita
Subject: Re: [dita] How much flexibility do specializers have to make
exceptions to behaviors that are outlined in the DITA standard?
 
On 10/15/07 4:39 PM, "Ogden, Jeff" <jogden@ptc.com wrote:
>  The question that is up for discussion is, are specializers free to do
>  anything they want or are there some things that the DITA Standard makes
>  out of bounds even for user defined specializations that aren't part of
>  the official DITA standard?
 
>  From my point of view, I'd like to see some limits on what specializers
>  can do in terms of referencing behaviors (what legal DITA URI's can look
>  like and what they mean), and when there are interactions such as
>  property cascading behavior between one document and another (from a map
>  to a topic or from a map to a map to a topic).  I want to increase the
>  likelihood that DITA users can share their documents, including
>  specialized documents, with others or move the documents into new
>  processing environments and still get good results.  I want to reduce
>  the amount of reimplementation users have to do when they share their
>  documents or move into new processing environments.
 
The DITA specification defines a number of core processing semantics that
constitute the core processing infrastructure that makes DITA both work
functionally (that is, when implemented, those features produce the result
that you presumably want because you're using DITA) and allows documents
and document processing to be reasonably interchangeable.
 
I think that this infrastructure includes the following:
 
- All addressing of DITA-governed content by DITA-governed content. That
is, you cannot, within a specialization, change the rules for resolving hrefs
(or any other DITA-defined addressing mechanism)) to DITA-based content.
 
- Conref. You cannot change the constraints or effective result that conref produces.
 
Where things start to get a little cloudier, and where I think this
discussion started, is in the area of the implications for topic references
and in particular how do topic references affect the effective properties
of the topics they reference?
 
The issue here is that while this area can be viewed as concrete in the
way that addressing and conref are, it can also be seen as a matter of
presentation style. For example, for some specializations of metadata used
within topicref I want their values to propagate and replace values on
referenced topics and for other values I do not. A blanket DITA-defined rule
of "metadata always propagates" or "metadata never propagates" would be
wrong some of the time so we can't define it. That leads to Paul's original
question of how can specializations express their intent in a case like
this that allows a tool like Arbortext Editor to do the expected thing
automatically? Clearly in this specific case there's a need for some sort
of schema-level way to indicate the processing intent.
 
Simple enough to design for this case, but how many cases are there?
Probably lots. That suggests you need a more general mechanism for this
sort of thing. That will be, necessarily, complex. Easier to just punt and say
"DITA has no opinion". But that doesn't help Paul. Seems like, for the
moment, there's no easy answer to this question.
 
At a minimum DITA has to define clear default behaviors for those areas
where processors can legitimately do different things.
 
I guess I would need to see some specific cases where a specialization
wants to deviate from either the defined or suggested behavior to evaluate
whether or not the deviation is processing or style, there's a way to usefully
parameterize the behavior choices or whether the requirement can be
satisfied in a different way. Or where, as above, DITA either says nothing
or isn't clear and there are multiple useful ways that a processor could
behave.
 
It's also worth saying that while DITA should "just work" that's always in
terms of the default behavior, whatever it is, as defined by the DITA spec.
Specializations that want something other than the default are on their
own and there should be no expectation on anyone's part that
specialization-specific stuff will magically happen without some
implementation effort.
 
In that respect, DITA-based applications are no different from any other
purpose-built XML application in that you may have to do a bit of local
customization of your generic tools to get what you want. However, with DITA
it should always be less (or no greater than) it would have otherwise been
because DITA gives you so much out of the box.
 
For example, for demonstration purposes I've defined a specialization of
reference for capturing animal field guide entries, including
specializations of <data for capturing the Linnaean classification of the
animals described. No DITA-aware processor is going to give me any special
support for authoring these classifications but I'd probably want to build
a little classification editor for these values since they need to be
validated and could be gathered from external data sources and whatnot. I
would not fault any DITA-supporting editor for not providing that but I
would expect a way to add it without too much difficulty.
 
Cheers,
 
Eliot
 
--
W. Eliot Kimber
Senior Solutions Architect
Really Strategies, Inc.
 
 
From: Michael Priestley [mailto:mpriestl@ca.ibm.com]
Sent: Thursday, October 25, 2007 3:41 PM
To: Michael Priestley
Cc: dita; Eliot Kimber
Subject: Re: [dita] How much flexibility do specializers have to make exceptions to behaviors that are outlined in the DITA standard?

Clarification:

in the href overriding example, a processor might choose to create a preview by summarizing specialized elements in a target's <refsyn> or equivalent, rather than using the <shortdesc>. This wouldn't affect the syntax of the href, but does change the expected processing from the default.

I realized in my wording below I used the word syntax twice to mean two different things :-)

Main point remains the same: I think everything in "expected behavior" is expected default behavior; everything in "expected markup/syntax" is required unless otherwise stated. The syntax for href and conref should be standard; the expected behavior should be default.

Michael Priestley
Lead IBM DITA Architect
mpriestl@ca.ibm.com
http://dita.xml.org/blog/25

 
> -----Original Message-----
From: Eliot Kimber [mailto:ekimber@reallysi.com]
Sent: Thursday, October 25, 2007 4:04 PM
To: Michael Priestley
Cc: dita
Subject: Re: [dita] How much flexibility do specializers have to make
exceptions to behaviors that are outlined in the DITA standard?
 
On 10/25/07 2:41 PM, "Michael Priestley" <mpriestl@ca.ibm.com> wrote:
> Clarification:
>
> in the href overriding example, a processor might choose to create a
> preview by summarizing specialized elements in a target's <refsyn> or
> equivalent, rather than using the <shortdesc>. This wouldn't affect the
> syntax of the href, but does change the expected processing from the
> default.
 
What you've described is rendition, not address resolution.
 
That is, when I say "addressing" I mean "the object that is addressed by the
href value" which is different with what you do with that thing once you have it.
 
That is, how or if you produce tooltips in some rendition is entirely a
matter of style. What those tooltips apply to (or at least what the initial
source of their ultimate value is) is a function of invariant address processing.
 
That is, you can choose to produce or not produce tooltips, you can't change
what "mytopic.dita#topicid/elementid" means from an address resolution standpoint.
 
[Note that this is one problem with DITA not using standard addressing
mechanisms: it provides no built in mechanism for choice in how you do
addressing at the fragment identifier level, which means you either have
non-DITA stuff or you use URIs that have to be interpreted by a specific URI
resolver. This is a fundamental problem with DITA 1.x that must be corrected
in DITA 2.]
 
> Main point remains the same: I think everything in "expected behavior" is
> expected default behavior; everything in "expected markup/syntax" is
> required unless otherwise stated. The syntax for href and conref should be
> default.
 
But the point is that that there are some things in DITA that are not
"expected behavior" but "required behavior", which includes, I assert, all
addressing and conref.
 
Cheers,
 
E.
 
--
W. Eliot Kimber
Senior Solutions Architect
Really Strategies, Inc.
 
 
From: Ogden, Jeff [mailto:jogden@ptc.com]
Sent: Thursday, October 25, 2007 6:18 PM
To: Michael Priestley; Eliot Kimber
Cc: dita
Subject: RE: [dita] How much flexibility do specializers have to make exceptions to behaviors that are outlined in the DITA standard?
 
Eliot, thanks for your comments and for getting this conversation started again.
 
In response to Michael’s comment/question:
> Couldn't an implementer decide that they want to limit reuse in their organization
> to content coming from specific directories? For example, check the conref path
> to ensure that it starts with "/reuse/"?
 
I don’t see a problem with this as long as the implementer is being more restrictive than what is required by the standard.  The standard says that conref values are URIs that reference DITA content with a number of checks to make sure they content being referenced is legal or is likely to be legal in the new context.  Limiting the references to a particular path isn’t violating that. The conref values that start with /reuse/ will always be valid URI and with a bit of luck the thing being referenced will be DITA content that is legal in the current content. An implementation will not have to do anything special to make the required checks. You can’t expect other implementations to impose the same limitations automatically, but that is OK.
 
  -Jeff
 
 
From: Michael Priestley [mailto:mpriestl@ca.ibm.com]
Sent: Thursday, October 25, 2007 6:22 PM
To: Eliot Kimber
Cc: dita
Subject: Re: [dita] How much flexibility do specializers have to make exceptions to behaviors that are outlined in the DITA standard?

I guess I was having trouble separating out "addressing" as a behavior from the various actual processes that use addressing. I see your point.

I was thinking of addressing as "what the syntax means" - for example topicid/elementid - we wouldn't want that to be overridden by processing, it's not even clear to me what overriding that would mean. But I buy that processing for addresses should not ignore or misinterpret the actual information in the address. That said, all the processes that do something with the info at that address should be overrideable - like shortdesc pulling, link creation, etc. etc.

For conref, which goes beyond the address, where do we draw the line? Is there a problem with my example? Or is it another case where the syntax's meaning is preserved, so even if the exact behavior as described in the spec doesn't apply it still is preserving the important part of the process, ie the meaning of the address?

As another conref example: we say you can generalize on the fly where necessary/appropriate - I can imagine someone overriding the generalization to, for example, generate titles for specialized sections that are being generalized during conref. Is that ok? Are there other conref overrides that wouldn't be ok, for example overriding the process to allow conref across specializations without generalization at all?

Michael Priestley
Lead IBM DITA Architect
mpriestl@ca.ibm.com
http://dita.xml.org/blog/25

The End