[XML-DEV Mailing List Archive Home] [By Thread] [By Date] [Recent Entries] [Reply To This Message] Is "xmlns:xml" legal or not?
Recently, I've run into a compatibility problem with some XML tools over whether it is valid to have an "xmlns:xml" declaration in a document. On close reading, the Namespaces spec says that namespace prefixes beginning with the (regular expression) pattern "[Xx][Mm][Ll]" are reserved, but it doesn't say that they are not allowed. Nonetheless, this has led to two different interpretations by tool vendors: 1. Flag all namespace prefixes starting the "[Xx][Mm][Ll]" as an error; 2. Allow "xmlns:xml" to be declared, but only allow it to be associated with the namespace URI "http://www.w3.org/XML/1998/namespace" (and do who knows what else for any other prefix starting with "[Xx][Mm][Ll]". I think we need to get a consensus on this one, and then (as necessary) push to have it added as an erratum to the Namespaces spec. This is too big a crack to leave unfilled, because if one tool adds "xmlns:xml" to a document, and another flags it as an error, less erudite users are just going to think that XML and/or XML tools are unreliable, and I don't want to see that happening (life's too short, etc.). As for my preference, having worked with tools that implement each interpretation, I think that allowing "xmlns:xml" to be defined (but only associated with a fixed [XML-version-dependent?] namespace URI) if actually easier for new users to understand than the alternative, that you may have to import the XML namespace to use "xml:lang", but you must not declare the prefix as you do for every other namespace. You thoughts and comments (to this list) would be very welcome. Cheers, Tony. ======== Anthony B. Coates (1) Content Distribution Architect - Project Gazelle (2) Leader of XML Architecture & Design - Chief Technology Office Reuters Plc, London. Tony.Coates@r... ======== ----------------------------------------------------------------- Visit our Internet site at http://www.reuters.com Any views expressed in this message are those of the individual sender, except where the sender specifically states them to be the views of Reuters Ltd.
|
PURCHASE STYLUS STUDIO ONLINE TODAY!Purchasing Stylus Studio from our online shop is Easy, Secure and Value Priced! Download The World's Best XML IDE!Accelerate XML development with our award-winning XML IDE - Download a free trial today! Subscribe in XML format
|