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Re: Error on generator-unable-to-provide-required-alt

From: Philip Taylor <P.Taylor@Rhul.Ac.Uk>
Date: Tue, 03 Sep 2013 10:31:32 +0100
Message-ID: <5225AC74.6080702@Rhul.Ac.Uk>
To: Leif Halvard Silli <xn--mlform-iua@xn--mlform-iua.no>, "Jan P." <proedie@arcor.de>
CC: www-validator@w3.org

> According to [1] 'A conformance checker must report the lack of an alt
> attribute as an error unless [...]: The img element has a
> (non-conforming) generator-unable-to-provide-required-alt attribute
> whose value is the empty string.'
> However, when I feed the following HTML code to the validator, it
> reports two errors.

> <!doctype html>
> <html>
> <head>
> <meta charset="utf-8">
> <title>Test</title>
> </head>
> <body>
> <img src="picture.jpg" generator-unable-to-provide-required-alt="">
> </body>
> </html>

> The errors are: 'An img element must have an alt attribute, except under
> certain conditions. For details, consult guidance on providing text
> alternatives for images.' (Which I did, obviously.)
> And: 'Attribute generator-unable-to-provide-required-alt not allowed on
> element img at this point.' (You don't say.)
> Shouldn't there be only a warning or did I miss anything? Thanks so much
> in advance.

I am confused; if you are able to get at the internals of the generator
so as to force it to omit the (completely ridiculous and non-conforming)
"generator-unable-to-provide-required-alt" attribute, why can you not
instead force it to omit a (normal and completely conforming "alt"
attribute with either a semantically useful value (e.g., "Picture of
a Royal Albatross") and if that is not possible (because the generator
is entirely automated and has no knowledge of the subject matter of
the image) a semantically valid but less useful value such as "Image
contents unknown to generator" ?

Philip Taylor
Received on Tuesday, 3 September 2013 09:31:52 UTC

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