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problems with Checkpoint 2.1

From: Al Gilman <asgilman@iamdigex.net>
Date: Thu, 01 Feb 2001 12:21:55 -0500
Message-Id: <200102011710.MAA1957098@smtp2.mail.iamworld.net>
To: w3c-wai-ua@w3.org
There has been some rewrite done on Checkpoint 2.1 recently.  I have some
concerns about the current draft wording.

   2.1 Make all [158]content available through the user interface. As
          part of meeting this requirement, provide a view (e.g., a
          [159]document source view) of the [160]text portions of
          content. This is only required for formats defined by
          specifications that the user agent [161]implements.
          [Priority 1]

The above says that a text presentation is required for the intersection of 
  - text formats, and
  - formats implemted (i.e. for which the user agent has a player)

Intersection is the wrong logical function for this rule.  The text view
be for anything that is viewable as text, i.e. anything in a text format,
whether the UA has a player that can present it at a higher level of
or not.  An example would be an SVG graphic used in a web page.  The SVG
actually containts a lot of words, and the words are internally stored in a
legible form following the suggestions of the access note for SVG.  But the
User Agent doesn't implement SVG.  The user should be able to glance at the
source as text and find the natural language embedded there even 'though they
don't get the graphic rendition.  In addition to this, if the user has a
for the format of any object in the content, then the user must have the
to have that content rendered with that player.

Another application scenario is that if what the author of the SMIL thought
user didn't need is an audio track, then the user must have access to an audio
rendering of that object if the User Agent supports that type of audio format
at all.  The user should be able to chose from the full range of feasible
options, based on the formatting of the data and the formats implemented by

The user must have their choice including a) if it is a format that the User
Agent implements, the user must have the choice of formatted rendering and b)
if the format is a text format and the User Agent implements Internet Media
Type text/plain, then the user must have the choice of text presentation.  The
requirement is the union of these two, not the intersection. 

Another example:  If the document links to a stylesheet in text/css , and the
User Agent implements text/plain, then the user must be able to view the text
of the stylesheet whether or not the User Agent implements CSS.

<possible new>

   2.1 Make all [158]content available through the user interface. For formats
that the User Agent implements (see [162]checkpoint 6.2), make the content
available through the implemented rendering process   In addition, for all
ref]text formats, make a source text view available. [Priority 1]

[edit to reduce the note, perhaps.]

          Note: In general, user agents render content through the user
          interface according to the instructions of implemented
          specifications (see [162]checkpoint 6.2). However, some users
          may not be able to access this content, even when the user
          agent renders it according to specification (e.g., for scripts
          or style sheets). Therefore, this checkpoint includes the
          requirement that user agents make available raw text content
          (including attributes, style sheets, etc.) through the user
          interface. Although this view (which may be a [163]document
          source view) is an important part of a solution for providing
          access to content, it is not a sufficient solution on its own
          for all content. This checkpoint does not require that all
          content be available through every [164]viewport. See
          [165]guideline 5 for more information about programmatic access
          to content.
          [166]Techniques for checkpoint 2.1

AG::  Insert definition at end of [new ref]

Text formats:  This includes the following two subcategoies.  First,all media
objects given an Internet Media Type of 'text', that is text/plain, text/HTML,
text/* or text/anything.  Second, all SGML and XML applications regardless of
Internet Media Type, including HTML 4.01, XHTML 1.1, SMIL, SVG, etc.
Received on Thursday, 1 February 2001 12:10:19 UTC

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