On Mon, Apr 18, 2016 at 2:10 AM, Stefan Monnier 
<monnier@iro.umontreal.ca> wrote:
> The nxml mode knows how to read a relaxng schema which describes the
> valid grammar of a given kind of XML document.  E.g. it can use it to
> give you things like context-aware completion of xml elements
> and attributes.
> 
> Emacs comes with the relaxng schema for HTML4 and there's a relaxng
> schema for HTML5 in GNU ELPA.
> 
> So nxml can provide in an automated way most of what's in
> html-tag-alist.
> 
> 
>         Stefan

I see, thanks for the explanation. It sounds like a good idea.

-- Simen