- From: Laura Carlson <laura.lee.carlson@gmail.com>
- Date: Fri, 9 Apr 2010 10:37:25 -0500
- To: John Foliot <jfoliot@stanford.edu>
- Cc: HTML Accessibility Task Force <public-html-a11y@w3.org>, Janina Sajka <janina@rednote.net>, "Michael(tm) Smith" <mike@w3.org>, Michael Cooper <cooper@w3.org>, Judy Brewer <jbrewer@w3.org>
Hi John, > Your Change Proposal states: > "When the validator flags missing text alternatives it creates a teachable > moment. A moment of great opportunity: a time to flag errors, educate, to > make people aware, and to get action, to get people to actually fix their > pages. > > I don't see anything in the resolution that takes this away, Oh but it does. * An error is something that is invalid. * A warning is something that is valid. Big difference. As Jonas said a while back the W3C HTML4 validator has done worlds more than the HTML4 specification for increasing the quality of HTML documents on the web. I have seen that an error over a warning makes a big difference in getting students and developers to fix their pages. An error gets attention. A warning doesn't. I have witnessed it time and time again in the classes that I teach and my work with developers. It is widely known that users rely on defaults in many areas of user interface design. They rarely customize. Defaults have power. [1] Errors are reported by default. Warnings aren't. Case in point is with the CSS Validator. Developers now have to go to "More Options" then "All" from the "Warnings" drop down menu to even enable warnings. For classes I give directions but many still mess up or forget. When the W3C validator throws an error for a missing alt the students and developers that I work with, finally get it through their heads that text alternatives are mandatory not just for WCAG but as well for valid HTML. It makes a BIG impression. It is also about teaching the structural integrity of the language. Requiring a set of programmatically valid options helps ensure that images have complete structure. Complete structure requires both src and text alternatives. src is to sighted users as text alternatives is to some users with disabilities. * Omit the src attribute and sighted users have no content. * Omit text alternatives and some users with disabilities have no content. Without both a src and a text alternative the <img> element is incomplete. They are both wrong. They are both errors. Lowering standards will lower accessibility. I've tried to address this in the rationale section of the change proposal: http://www.w3.org/html/wg/wiki/ChangeProposals/ImgElement20090126#Rationale Any suggestions for improvement appreciated. > in fact as I > read it, it re-enforces this aspect: take advantage of the teachable moment > and get out the appropriate resources. Ian had already added a link to WCAG as I asked for in Bug 9241. Best Regards, Laura -- Laura L. Carlson [1] http://www.useit.com/alertbox/defaults.html -- Laura L. Carlson
Received on Friday, 9 April 2010 15:37:58 UTC