- From: Al Gilman <Alfred.S.Gilman@IEEE.org>
- Date: Wed, 25 Feb 2004 10:41:05 -0500
- To: <w3c-wai-gl@w3.org>
- Cc: wai-liaison@w3.org
[this is from an exploratory discussion (not consensed position, but informed by past PF experience) to the HTML WG. Jens said 'abbr' is too narrow to absorb the use cases of 'acronym.' In the view of the HTML WG it is not. In XAG we suggest a) do make your markup names suggestive of the meaning, yet b) never rely on the heuristic value of the markup name as the definition of the construct. It is reasonable, at the cost of re-training pain, to redefine 'abbr' to fit all uses of 'abbr' and 'acronym' in the past. Anyhow, here is a sample (to be followed by another, more top-town post from Matt) from our attempts to negotiate a better future in this area on your behalf. -Al] -- on the product: I submit that there are plenty of use cases in DI and WAI that qualify abbreviations and their expansions as 'conditional content' in the language of the UAAG10. I have tried to substantiate that below. [...] -- details follow [...] Let me try to establish that abbreviations, the choice of when to use them in presentation, and their synonymous relationship with their expansions, are a 'posterkid,' a 'classic' case of what WAI wants from XHTML2 -- markup that exposes a *content* model supportive of *later* decisions for the purpose of the adaptation of presentation. I mean... what can I say? You have heard the expression "say what you mean, not what to do with it"? In terms of those memorable words, 'lookup' is precisely "what to do with it." We don't need any more content models designed around one use case. Consider another appearance of the abbreviation concept in HTML4: <quote cite= "http://www.w3.org/TR/1999/REC-html401-19991224/struct/tables.html#adef-abbr"> abbr = text [CS] This attribute should be used to provide an abbreviated form of the cell's content, and may be rendered by user agents when appropriate in place of the cell's content. [...] </quote> This specification language makes it clear that html4:th.abbr creates "alternate content" which in UAAG we have appropriately generalized to "conditional content" just as html2:img.alt does. So at least this instantiation of the 'abbreviation' concept in the minds of the spec authors involves content selection. And I submit that the practice of using html4:abbr.title to provide an expansion for html4:abbr.content is for all practical purposes the same relationship in reverse. What I would nominate as a possible content model for the abbreviation relationship is as follows: There are two things, A, and B A isA string B isA string lengthInCharacters(A) << lengthInCharacters(B) denotationalValue(A) = denotationalValue(B) If these things are satisfied, then colloquially we would say A is an abbreviation for B B is the expansion for A Consider the button bar in your browser. It has presentation options. The presentation options in many cases are: string, image, or image+string. This is content selection, it is deliver-context-driven adaptation. I am not trying to get to ultimate truth, here about what is 'content.' I mean *in the persistent 'source' XML representation* the image and the text are in separate data forks in the XML infoset. But all three presentations have the same denotational function. We need to capture the range of choice that captures the necessary population constraints so that the intended notion *does* get presented *somehow.* Consider the standard editing practice of presenting the abbreviation as an annotation on the expansion at the first instance, and the abbreviation in lieu of the expansion thereafter. This is content selection. There are both the short and long strings. After initializing the users' recall with the bond between them, the short one is used to allude to the long one. This is context-dependent content selection. In addition to supporting a 'expand on query' lookup function for abbreviations, would it not make sense to automate, or 'push' the display of the expansion the first time an abbreviation is visited, when a Web visitor arrives at an internal anchor in the resource and hence cannot be presumed to have ingested the abbreviation's denotation? [...] In Device Independent authoring and view extraction, the short and long forms are conditional content. On a big-screen desktop one will format a left-column navigation bar with full-image icons plus the long text forms. On a WAP1 tinyBrowser, one will use either the short text abbreviation or a line-drawing simplified icon. The XML Format in which the content fragments are stored needs to know, conclusively, that all these alternative content items (they will be in parallel data) are used as indications of the same thing. And that the view-formulating scripts [general sense] may pick and choose among them as appropriate. The screen reader or other assistive technology on the client's computing platform needs access to the full content model to make the same sort of view-adaptation decisions as the DI adaptation engine is making [typically] on the server side. In particular, in the screen-reader delivery context, there are a number of behaviors, and we need to have the content cues to guide the client-side decision as to which of these to follow (in combination with user cues such as mode settings for general rules): - replace the text with a sound in an associated: .. sounds-like text .. audio file, or .. phone-stream - pronounce the element content text as if a word in the current xml:lang value - spell out the element contents - say the words in an associated expansion The choice will be guided by client-side information as to - is the text being rendered in Braille or audio? - has the user selected vebose or terse explanation? Note that achieving the full range of "behaviors that should be selectable" it take a blend of "conditional content" data and "rendering" perturbations on presentation of the data. - speaking the expansion selects conditional content .while. - spelling the element content uses a 'spell' mode control in the TTS rendering engine An optimized screen-reader UI would have verbosity mode controls comparable to what the standard digital talking book provides that govern the handling of abbreviations vs. expansions in the [push] presentation [plus embedded pull opportunities]. A similar range of modes should be available concerning the expansion of terms, be they abbreviations or jargon, to readers in a second language, or a second discipline. http://www.niso.org/standards/resources/Z39-86-2002.html#Skip Lookup is a behavior, a use case. It is the appropriate display-control protocol in a common delivery context. But it is not a 'pure' content model and it is not the appropriate behavior in all delivery contexts for the same content model, that is to say for the same semantic relationship between two content fragments. To support adaptive presentation that adapts appropriately across diverse delivery contexts, including the disability cases as a natural part of the built-in flexibility, we need tools for both parallelizing the content and tuning the presentation transform. [content selection is one of the capabilities supporting tailoring the composed adapted view.] We need content markup that clearly characterizes conditional content so that the device-adaptive server and the content-reprocessing Assistive Technology have the control degrees of freedom and data alternatives they need to achieve a) a functional or b) a commercially competitive presentation. [...] Best regards, Al
Received on Wednesday, 25 February 2004 10:41:14 UTC