- From: Bruce Bailey <bbailey@clark.net>
- Date: Tue, 7 Dec 1999 18:44:31 -0500
- To: "'Wendy A Chisholm'" <wendy@w3.org>, Charles McCathieNevile <charles@w3.org>
- Cc: "w3c-wai-gl@w3.org" <w3c-wai-gl@w3.org>, "w3c-wai-er-ig@w3.org" <w3c-wai-er-ig@w3.org>
I thought the consensus was that alt=" " (and even alt=" " [or more spaces]) is, strictly speaking, not valid html (because of the whole leading/trailing-spaces-may-be-ignored thing) but that this did not trip up any known browsers. The consensus was that alt=" " (or any number of spaces) should probably be rendered the same way as alt=" ", but browser behavior on this point was variable. I also thought the consensus was that alt=" " is NOT the same thing as alt="" no matter what the interpretation. My version of Lynx (pretty new, but maybe not the very latest) treats alt="" VERY differently than alt=" ". According to working draft of the WAI UA guidelines, alt="" SHOULD hide the image (and any associate link). This IS what my version of Lynx does. I don't think the difference between alt="" and alt=" " is author preference. It is more an obscure technical issue. We can "trump" the whole issue by deciding that alt="" should NEVER be allowed by the WCAG. This is an overly zealous rule. It has the virtue of being very simple. We can leave the validity of alt=" " to the validation services (they don't currently report an error). I don't think, in practice, you should flag for alt=" " since then you must also test for all permutations of   and spaces. Certainly this kind of test can be put into an algorithm, but if an author thinks that their alt text is best represented by (some form of) spaces, who are we to question that? We don't actually have a test for GOOD alt text (without human intervention anyway) except for the obvious things like alt="foo.gif (1234 bytes)". My point is, if the author goes to the trouble of inserting alt text (even alt=" ") then they must have thought about it for a second or two. This is what we are trying to promote! There are no authoring products that generate alt=" " for you, although some do generate alt="" and stuff like alt="foo.gif (1234 bytes)". For spacer gifs, alt=" " is logical, whereas alt="" is ALWAYS questionable. It is not possible to tell if alt="" is by design or accident. This is NOT true for alt=" ". --Bruce On Tuesday, December 07, 1999 6:14 PM, Wendy A Chisholm [SMTP:wendy@w3.org] wrote: > At 01:02 PM 12/7/99 , Charles McCathieNevile wrote: >> 3b. THere is no defined handling for alt=" ", so it might no have the desired >> effect > > using "" versus " " has been argued back and forth. It is my > interpretation of sifting through the archives that if the "desired effect" > is a space between two characters, using an image for this is > inappropriate. We suggest style sheets. > > Also, some people have favored "" while others like " ". Most of the > arguments have been based on the current state of the art handling of > spaces. However, it appears that "" and " " are currently handled the same > [http://www.w3.org/WAI/GL/tests/spaces.html]. I was the only one to > respond to the tests, so it only includes the 3 browsers I was able to test. > > Many people pointed to the HTML4 spec where it says that "leading or > trailing spaces" may be ignored. However, is a single space trailing or > leading? > > is inappropriate since it is intended to be used as a typesetting > hint as Nir described on 17 November: > http://lists.w3.org/Archives/Public/w3c-wai-gl/1999OctDec/0070.html > Alan Flavell also makes a good point about nbsp not being considered "white > space" http://lists.w3.org/Archives/Public/w3c-wai-gl/1999OctDec/0069.html > > Therefore, I don't think it matters much if we suggest that people use "" > or " ". Personally, it seems to be a matter of author preference. Neither > one is going to cause horrible things to happen (although "" has > historically - i.e. it supposedly used to be ignored by Lynx but doesn't > seem to be anymore). > > If we look at the long term, I would suggest using a space since spaces are > supposed to be preserved in XML. However, I also agree that it is a matter > of separating content from presentation. A space seems to say, "there is > formatting going on here" while null says, "it's decorative." > > Again, I think it boils down to author preference. > > >3d. If the image is decorative, use alt="" but ask if the author would like > >to associate a longdesc > I think it is up to the author, thus why I left it as either a blank or a > short description. It is my understanding that some users appreciate > knowing what is on the page. If the author wants to support short > descriptions for them, it is their choice. > > As we look forwards to tools that will allow users to navigate the > structure of a page, if a user chooses to navigate past images then we > won't have to worry as much about users wading through alt-text that they > don't care about.
Received on Tuesday, 7 December 1999 18:47:05 UTC