Re: [Lynx-dev] @longdesc support in Lynx

[Leif Halvard Silli]

Thomas Dickey, Tue, 12 Oct 2010 20:32:22 -0400 (EDT):
> On Wed, 13 Oct 2010, Leif Halvard Silli wrote:
> 
>> Lynx  currently has no support for @longdesc.
>> @longdesc provides "link to long description (complements alt)".
>> See: http://www.w3.org/TR/html4/index/attributes.html
>> Example: <img alt="Chart fo the development"
>> longdesc="description-of-chart" src=i.jpg >
> 
> quoting:
> 
> longdesc = uri [CT]
> This attribute specifies a link to a long description of the image. 
> This description should supplement the short description provided 
> using the alt attribute. When the image has an associated image map, 
> this attribute should provide information about the image map's 
> contents. This is particularly important for server-side image maps. 
> Since an IMG element may be within the content of an A element, the 
> user agent's mechanism in the user interface for accessing the 
> "longdesc" resource of the former must be different than the 
> mechanism for accessing the href resource of the latter
> 
> So - it's a link, to someplace, and the guideline says it's not to be 
> followed as if it were an href.  So that leaves inline display, or 
> some special keystroke.

I guess "special keystroke" fit with working like a image map link?  
(That is should be implemented like an image map link is my new "baby" 
...) ;-) Image maps in Lynx, Elinks etc are only revealed when you 
press the right arrow while the insertion point is above the @alt text. 
Thinking about @longdesc as an "invisible" (to sighted) image map 
creates a patters that is easy to understands. In addition, text 
browsers already have fine support for image maps, which means that you 
perhaps can reuse some code or at least understand how to implement it.

Btw, I also filed it as bug: 
http://savannah.nongnu.org/bugs/index.php?31319

>> Any chance that Lynx, with its history as a accessibility web browsers,
>> could implement @longdesc support?
> 
> How much is it used?  (Looking for examples...)

This page lists 98 examples, I have been told. 
http://www.d.umn.edu/~lcarlson/research/ld.html

The page also collects, as much as possible, any useful info there is 
on @longdesc. The goal of the page is to justify @longdesc's inclusion 
in HTML5.

It is not as much used as it should, because support is not universal. 
But Opera, iCab (webkit browser) have GUI level support. Webbie - an 
accessibility IE shell browser  - present longdesc links as links. 
Well, you can just read the above page to learn about support. :-) 
Internet Explorer and Firefox also implements @longdesc, kind of - at 
least to the degree that Jaws and other Assistive Technology (AT) can 
us it to implement support in.

So, having support in Lynx would - to be honest - be another thing that 
could bolster @longdesc's case in HTML5. 
-- 
leif halvard silli