W3C home > Mailing lists > Public > www-svg@w3.org > October 2008

[1.2T-LC] 16.2.9 values attribute 'extended syntax'

From: Dr. Olaf Hoffmann <Dr.O.Hoffmann@gmx.de>
Date: Wed, 1 Oct 2008 16:00:38 +0200
To: www-svg@w3.org
Message-Id: <200810011600.38301.Dr.O.Hoffmann@gmx.de>

Hello SVG WG,

it is surprising, that there is already a lot of SVGT1.2 content with invalid
values for the 'values' attribute, because such 'extended syntax' is nonsense
both for SMIL and for SVG1.1 too.
For me this indicates more simple errors from authors or editors, especially
because the adobe plugin, for several years the most used viewer for animated
SVG content has a quite different '(error) management' for such wrong syntax
(if it is wrong and does not specify an allowed empty value, it indicates an
error and assumes one more value than the number of semicola. If an empty
value is possible, an empty value is correctly interpreted as empty value).
Every author testing content with the adobe plugin should have noted
the error and should have already fixed it before publication.
Typically if I find errors in my documents or scripts, I simply fix them and
do not expect, that the specification is modified to fix my own errors. 
And even more, no one can expect, that the behaviour of already published
versions of viewers can be modified, therefore this 'extended syntax' should
never be used to ensure better backwards compatibility with older viewers,
therefore such a superfluous trailing semicolon needs to be fixed anyway to
ensure a predictable behaviour.
Especially there is no benefit for authors or users from this 'extended
The opposite is the case with something like "/a.txt; ; /b.txt; ;" to get the
desired effect of an  empty list item only for SVGT1.2.
For implementors of SVG1.1, SVGT1.2 and SMIL it gets even worse, because 
they have to implement it differently for SVGT1.2 without any advantage for

My suggestion is to skip this SMIL and backwards incompatibility completely
and to help authors to fix their documents, if it is known, which authors
produce so much erratic content without testing it.
If such content is already mentioned in the specification, some editor should
know at least some of these authors and how much invalid content it is. Maybe
references would be useful too for others interested in helping those authors.
This is more friendly for those authors as to brand or to stigmatise them to
be guilty to corrupt the well thought out SMIL syntax.

Received on Wednesday, 1 October 2008 14:07:49 UTC

This archive was generated by hypermail 2.4.0 : Friday, 17 January 2020 22:54:20 UTC