Cascading styles

[Lars Magne Ingebrigtsen <larsi@gnus.org>]

We should probably implement (at least) text-decoration, text-transform
and font-style, and do the cascading thing.  But a thing just occurred
to me.

<p style="color: black;"><p style="color: white;">Foo</p></p>

will first make Foo white, and then black.  So, er, either the overlays
should be applied in reverse-stack-order, or `shr-insert-*-overlay'
should avoid clobbering overlays that are already there, and that use
the same properties (i.e., :foreground, etc).

The latter seems easier.

But what I wanted to talk was the CSS inheritance thing and non-inline
style sheets.

So here's my thought:

shr should parse the style sheet first, and bind the thing at the
top-most level, like:

(defun shr-insert-document (dom)
  (let ((shr-stylesheet (shr-parse-stylesheets dom)))
    ...))

or something.

And then we'd have

(defun shr-descend (dom)
  (let ((shr-stylesheet (append (shr-parse-style (cdr (assq :style (cdr dom))))))) ...
  
So you'd inherit down into the DOM and pop when you exit.  However,
would that be correct?  Er, no, not really.  So you'd basically have the
inline thing, plus the stylesheet, but not endlessly combining inline
things.

And I'm not sure this is worth doing...  I mean, implementing it is
probably easy, but computation-wise for the user...
  
-- 
(domestic pets only, the antidote for overdose, milk.)
  larsi@gnus.org * Lars Magne Ingebrigtsen