Re: A nit and an addition for the current draft

Bert Bos (bert@let.rug.nl)
Mon, 18 Sep 1995 13:43:56 +0200 (METDST)


Steve Grimm writes:

|The nit: The text-background attribute has an ambiguous value type.
|
|<style>
| body: text-background="bluegreen"
|</style>
|
|There's no way for a parser to know if "bluegreen" is a relative URL or a
|color name. Perhaps there should be two attributes for background, with a
|defined order of precedence between them.

The intention is that color names are entered as keywords without
quotes. The reasoning behind this is, that, presumably, the number of
color names is small, so they can be entered in the parser's hash
table.

|The addition: I think it's critical, if we want stylesheets to be adopted
|widely, that they provide a superset of the presentation control that the
|Netscape HTML extensions do. One glaring omission is an equivalent to the
|"border" attribute of the <img> tag. There's no way for a document author
|to specify that a hyperlink on an image be displayed with no decoration.
|
|Maybe "image-border", whose value is a size in any of the usual units.

For floating images, there is a `border' property (actually a set of
related properties), that can do this and much more. But because of
its generality (and therefore complexity), it was left out of level 1.

For inline images, there is currently only text-line (provisional
name). We forgot to specify that `border' applies to included material
as well. This should be fixed.

But: this is an example of a general problem with level 1: it has to
be both simple and compatible with level 2. Since we don't want to
compromise level 2 because of level 1, this double goal may be
impossible to attain, unless we accept that there are implicit
formatting rules for HTML that are not expressible in CSS level 1.

Maybe we can find a restricted syntax for the margin property that is
simple enough for level 1 and upwardly compatible, but I'm afraid that
won't be very easy.

|On a related note, there should also be a way to specify that two images
|should be displayed immediately adjacent to one another, with no space
|inserted. Some browsers insert extra space even if they don't render a
|link border (notably NCSA Mosaic for Windows.)

This is handled by the same `border' properties. The default is no
border.

Btw. is a line break allowed before/after an image?

Bert

-- 
                          Bert Bos                      Alfa-informatica
                 <bert@let.rug.nl>           Rijksuniversiteit Groningen
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