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RE: Conditional versus Optional: Preliminary Observations

From: Hansen, Eric <ehansen@ets.org>
Date: Fri, 23 Feb 2001 19:25:13 -0500
To: "'Jon Gunderson'" <jongund@uiuc.edu>, "Hansen, Eric" <ehansen@ets.org>
Cc: "'oedipus@hicom.net'" <oedipus@hicom.net>, w3c-wai-ua@w3.org
Message-id: <B49B36B1086DD41187DC000077893CFB8B486D@rosnt46.ets.org>
I agree with the idea that discerning authors intent is not an exact
science. I discussed briefly with Ian and I think that he may propose a
revision. Good points...

> -----Original Message-----
> From: Jon Gunderson [mailto:jongund@uiuc.edu]
> Sent: Friday, February 23, 2001 1:39 PM
> To: Hansen, Eric
> Cc: 'oedipus@hicom.net'; w3c-wai-ua@w3.org
> Subject: RE: Conditional versus Optional: Preliminary Observations
> 
> 
> It seems it might be better to reference the specification 
> rather than the 
> author for what is "conditional" content.  So maybe something like:
> 
> <NEW DEFINITION>
> Conditional content is content defined through specification.  Some 
> conditional content has a direct relationship to 
> accessibility, and other 
> conditional content is used for accessibility information and 
> other types 
> of information.  The inclusion of conditional content by an 
> author may or 
> may not be required by a specification for the content to be 
> considered 
> valid.  Even though a specification may not require the 
> author to include 
> conditional content, author specified conditional content may 
> be required 
> for the resource to be considered accessible.  Specifications 
> typically do 
> not require that conditional content be rendered by default, 
> but that it 
> must be made available to the user through the user interface 
> under certain 
> conditions. Rendering conditions for conditional content 
> include, but are 
> not limited to, user agent capabilities, user preferences and 
> bandwith 
> available for communication.  For accessibility user preferences is 
> typically the condition that is used for conditional content 
> needed for 
> accessibility is rendered.  Some mechanisms for providing conditional 
> content include the "alt" attribute and the OBJECT element in 
> HTML, and the 
> test attributes of SMIL 1.0 and SMIL 2.0.  The rendering 
> semantics (when 
> and where) of conditional content may be well-defined in some 
> cases (e.g., 
> "alt" and OBJECT in HTML) and less well-defined in others 
> (e.g., "title" in 
> HTML).
> </NEW DEFINITION>
> 
> Something about authors "intent" bugs me, I am not sure what. 
>  If an author 
> uses the IMG element of HTML then I guess that signifies that 
> the author 
> expects the user to view the image, but I don't know why we need to 
> understand the authors intent for this conditional content 
> definition to be 
> useful.  I think the definition should emphasize that access 
> to conditional 
> content is needed for accessibility and not try to understand 
> the authors 
> intent.
> 
> Jon
> 
> At 12:10 PM 2/23/2001 -0500, Hansen, Eric wrote:
> >I think that removing the notion of 'intent' from the definition of
> >optional/conditional content is troublesome due to the fact the that
> >definition, even without the change, is arguably already too 
> broad. My gut
> >feeling is that to remove the constraint of intent would 
> push the definition
> >over the edge, making it much too broad.
> >
> >Consider a possible example of the current broadness of the 
> the definitions.
> >Think of a sequence of Web pages, each linked to the next. 
> The first page is
> >presented by 'default'; the succeeding pages are only presented under
> >certain conditions or circumstances. Does that make the 
> succeeding pages
> >'conditional content'?
> >
> >The current definition does not say much about the grain 
> size of these
> >chunks of content (really only through the examples).
> >
> >By removing the notion of intent, then doesn't one make the 
> scope all the
> >broader. Let us consider your suggested definition.
> >
> >I
> > > think we say that it is content the author provides that will
> > > be rendered
> > > given a certain set of circumstances that include user agent
> > > capabilities,
> > > user perferences and the bandwidth of the informational exchange.
> >
> >Especially if we consider that 'user preferences' might 
> include liberal
> >access to content through a source view, then under this 
> definition is there
> >any information that would _NOT_ be optional/conditional 
> content? Maybe not.
> >And if that this the case, then the term 
> 'optional/conditional content' is a
> >distinction without a difference and we really should be saying 'all
> >content'. But I don't think that we mean 'all content' where 
> we refer to
> >'optional/conditional content. So, at this point I would be 
> concerned about
> >removing reference to intent.
> >
> >I think that if intent were removed we would need to look at 
> adding other
> >constraints, such as information about grain-size of these chunks of
> >content.
> >
> >
> > > -----Original Message-----
> > > From: jon gunderson [mailto:jongund@ux1.cso.uiuc.edu]
> > > Sent: Thursday, February 22, 2001 11:38 PM
> > > To: Hansen, Eric
> > > Cc: 'oedipus@hicom.net'; w3c-wai-ua@w3.org
> > > Subject: RE: Conditional versus Optional: Preliminary Observations
> > >
> > >
> > > I don't think we need to mention the authors intent in the
> > > definition.  I
> > > think we say that it is content the author provides that will
> > > be rendered
> > > given a certain set of circumstances that include user agent
> > > capabilities,
> > > user perferences and the bandwidth of the informational exchange.
> > >
> > > Jon
> > >
> > >
> > > On Thu, 22 Feb 2001, Hansen, Eric wrote:
> > >
> > > > Gregory,
> > > >
> > > > The suggestion is interesting. If the change were made,
> > > would the definition
> > > > capture what we mean?
> > > >
> > > > New, tentative definition of "Conditional content":
> > > >
> > > > Conditional content is content that the author does not 
> intend the
> > > > user agent to render by default, but that the author does intend
> > > > to make available to the user through the user interface under
> > > > certain conditions. Some mechanisms for providing conditional
> > > > content include the "alt" attribute and the OBJECT element in
> > > > HTML, and the test attributes of SMIL 1.0 and SMIL 2.0.
> > > >
> > > > The rendering semantics (when and where) of conditional 
> content may
> > > > be well-defined in some cases (e.g., "alt" and OBJECT in HTML)
> > > > and less well-defined in others (e.g., "title" in HTML).
> > > >
> > > > Note: The Web Content Accessibility Guidelines 1.0 requires that
> > > > authors provide text equivalents for non-text content. This is
> > > > generally done by using the conditional content mechanisms of a
> > > > markup language.
> > > >
> > > > Thanks!
> > > >
> > > > - Eric
> > > >
> > > > Old defintion of "Optional content" per
> > > > 
> http://lists.w3.org/Archives/Public/w3c-wai-ua/2001JanMar/0249.html
> > > >
> > > > -------------------------------------------------
> > > > Part III: Definition of optional content
> > > > -------------------------------------------------
> > > >
> > > > Optional content is content that the author does not intend the
> > > > user agent to render by default, but that the author does intend
> > > > to make available to the user through the user interface under
> > > > certain conditions. Some mechanisms for providing optional
> > > > content include the "alt" attribute and the OBJECT element in
> > > > HTML, and the test attributes of SMIL 1.0 and SMIL 2.0.
> > > >
> > > > The rendering semantics (when and where) of optional content may
> > > > be well-defined in some cases (e.g., "alt" and OBJECT in HTML)
> > > > and less well-defined in others (e.g., "title" in HTML).
> > > >
> > > > Note: The Web Content Accessibility Guidelines 1.0 requires that
> > > > authors provide text equivalents for non text content. This is
> > > > generally done by using the optional content mechanisms of a
> > > > markup language.
> > > >
> > > > > -----Original Message-----
> > > > > From: oedipus@hicom.net [mailto:oedipus@hicom.net]
> > > > > Sent: Thursday, February 22, 2001 4:58 PM
> > > > > To: w3c-wai-ua@w3.org
> > > > > Subject: Conditional versus Optional: Preliminary Observations
> > > > >
> > > > >
> > > > > Conditional versus Optional: Preliminary Observations
> > > > >
> > > > > in the minutes from the 22 February 2001 telecon
> > > [reference 1], the
> > > > > following exchange was recorded:
> > > > >
> > > > > quote
> > > > >   GR: "Required optional content" is a little weird.
> > > > >
> > > > >   IJ: Good point!
> > > > >
> > > > >   Action IJ: Find clearer wording.
> > > > >
> > > > >   GR: I propose changing "optional content" to
> > > "conditional content".
> > > > >       I think that conditional doesn't presume that 
> one form of
> > > > >       content is preferred over another.
> > > > >
> > > > >   IJ: I don't think "optional" suggests that optional content
> > > > >       is lower class.
> > > > > unquote
> > > > >
> > > > > 1. required bits are not "optional"--"required optional" is an
> > > > > oxymoron; what is "optional" is the discretionary portion of
> > > > > the requirement--for example, in the HTML4/XHTML 
> world, deciding
> > > > > on appropriate ALT text for the IMG element...  the A, the L,
> > > > > the T, the equals sign, and a pair of quotes are 
> required--what
> > > > > goes between the quotes is the optional bit...
> > > > >
> > > > > 2. "conditional" because what is delivered to the 
> requesting UA
> > > > > is the derivative of the conditions surrounding slash 
> containing
> > > > > slash initiating the transaction; moreover, the 
> conditions under
> > > > > which content is delivered (or in which content is capable of
> > > > > being delivered) are not always/necessarily 
> "optional", as they
> > > > > may (or are quite likely to) include both those over which the
> > > > > user has either no or limited control, or of which the user is
> > > > > ignorant (in a non-pejorative sense)--conditions can also be
> > > > > predicated upon explicit user choice; server side filters and
> > > > > transformations, including processing by proxy servers;
> > > > > configurations slash settings; hardware limitations; language
> > > > > preference (accept) settings; functional limitations,
> > > > > environmental limitations; markup support slash standards
> > > > > compliance ; etc.; the point is that the "content" 
> (the message)
> > > > > is capable of being delivered by a number of 
> potential messengers
> > > > > (content/file types), depending upon which is most 
> appropriate--
> > > > > e.g. when certain conditions (no matter their source) 
> apply, send
> > > > > slash receive slash expose slash render X, not Y or 
> Z, but if X
> > > > > does not exist slash has not been provided, Q will be
> > > acceptable...
> > > > >
> > > > > 3. "conditional" is completely neutral--no need to speak of
> > > > > equivalencies; doesn't champion slash pit one form of content
> > > > > slash modality over another, as it doesn't matter why the
> > > > > conditions exist, only that the UA respond to them
> > > > > appropriately, by providing content in the most appropriate
> > > > > content-type slash form slash modality, whether due to an
> > > > > explicit request for a particular content type, the explicit
> > > > > exclusion of unsupported slash unusable slash unwanted content
> > > > > types, or by preference slash cascade order
> > > > >
> > > > > 4. the term "conditional" captures the nuances of the term far
> > > > > more concretely, and far less ambiguously, than "optional", as
> > > > > it incorporates user configuration; negotiation transactions
> > > > > (such as those based on CC/PP, accept headers, etc.); SWITCH-
> > > > > and SWITCH-like mechanisms; the rendering order of nested
> > > > > OBJECT elements; SMIL test attributes; and the CSS cascade, to
> > > > > name but a few
> > > > >
> > > > > 5. "optional" is a dangerous term because the plain English
> > > > > language definition of the word "optional" is, according to
> > > > > the online edition of Webster's (http://www.m-w.com)
> > > > >
> > > > > quote
> > > > >   involving an option : not compulsory
> > > > > unquote
> > > > >
> > > > > which (at least to my ears) eliminates the term from 
> contention,
> > > > > as use of the ALT attribute for the IMG element is 
> compulsory in
> > > > > HTML4/XHTML1...
> > > > >
> > > > > gregory.
> > > > >
> > > > > PS: i know that the example is technology-specific, but that's
> > > > > simply because the case of IMG is the most familiar 
> and clearest
> > > > > illustration of the point...
> > > > >
> > > > > References:
> > > > >
> > > > > [1] (long URI warning!)
> > > > >
> > > 
> http://lists.w3.org/Archives/Public/w3c-wai-ua/2001JanMar/0258.html
> > > > > -------------------
> > > > > Email sent using AnyEmail from http://www.hicom.net
> > > > >
> > > >
> > >
> 
> Jon Gunderson, Ph.D., ATP
> Coordinator of Assistive Communication and Information Technology
> Division of Rehabilitation - Education Services
> MC-574
> College of Applied Life Studies
> University of Illinois at Urbana/Champaign
> 1207 S. Oak Street, Champaign, IL  61820
> 
> Voice: (217) 244-5870
> Fax: (217) 333-0248
> 
> E-mail: jongund@uiuc.edu
> 
> WWW: http://www.staff.uiuc.edu/~jongund
> WWW: http://www.w3.org/wai/ua
> 
> 
Received on Friday, 23 February 2001 19:25:36 UTC

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