- From: Leif Halvard Silli <xn--mlform-iua@xn--mlform-iua.no>
- Date: Wed, 23 Jan 2013 10:11:49 +0100
- To: David Sheets <kosmo.zb@gmail.com>
- Cc: Henri Sivonen <hsivonen@iki.fi>, Daniel Glazman <daniel@glazman.org>, Sam Ruby <rubys@intertwingly.net>, Noah Mendelsohn <nrm@arcanedomain.com>, "www-tag@w3.org List" <www-tag@w3.org>, "public-html@w3.org" <public-html@w3.org>
David Sheets, Tue, 22 Jan 2013 21:18:00 -0800: > What is the reason that > <http://dev.w3.org/html5/html-xhtml-author-guide/#content-type> says > > <blockquote> > The HTTP Content-Type: header has no extra rules or restrictions, > whereas polyglot markup does not use the http-equiv="Content-Type" > declaration on the meta element. > </blockquote> The Polyglot Markup spec limits itself to define a subset of the HTML5 spec, which permits meta@charset=UTF-8 in both XHTML code and HTML code, whereas the HTML5 spec only permits meta@http-equiv in HTML code. > This suggests to me that putting something like > > <meta http-equiv="Content-Type" content="application/xhtml+xml" /> A case could be made for allowing 'text/html;charset=UTF-8' in XHTML5 since meta@charset has somewhat limited support outside the GUI browser world. For instance, Microsoft Word and Open Office doesn't support <meta charset="UTF-8"/>. Which, I have to admit, feels like a pain in polyglotâs robustness principle ass. ;-) But then again: If you export/download a Google Docs document (from Google Drive) as HTML, you will find that it contains no encoding declaration (and no DOCTYPE for that matter) - all the non-ASCII is converted to numerical character entities. > is a potential way to indicate to text/html consumers that this > representation is also parseable by an XML parser and interpretable by > an XHTML renderer. > > Is this ill-advised for some reason? Is there a pitfall here of which > I am ignorant? > > It would be nice to embed useful metadata indicating that the present > representation is intended to have identical semantics under different > media types' interpretations. This would give multi-modal consumers a > means to leverage both HTML and XML processing on the document if so > instructed. If you meant that one could include two meta based encoding decalraiton elements in the same document, then HTML5 forbids that as well. http://www.w3.org/html/wg/drafts/html/master/document-metadata.html#charset -- leif halvard silli
Received on Wednesday, 23 January 2013 09:12:21 UTC