Re: enriched-mode and switching major modes.

[Richard Stallman]

    Word
    processors assign properties to paragraphs, including defaults for
    character styles (like the font, the weight etc.); and they support
    style sheets for that.

Why can't we do something like that in Emacs using text properties?
We could perhaps have a text property on the whole paragraph
that indirects to a list of default properties, and then have other overriding
properties on specific characters in the paragraph.

Aside from data format, what would be the difference between a "style
sheet" and that list of default properties?

    It is very, very hairy to keep paragraphs,
    their properties and their representation in an Emacs buffer in sync,
    not to talk about style sheets.  In fact I do think that getting a WP
    UI right in Emacs is currently impossible.

Since you're saying something negative, I think you should fill in the
argument for this conclusion.  What methods have you considered?

    Indeed, I believe that in the long run Emacs' display engine should
    support a real block model.

Could you explain more clearly what you mean by that?