Re: TWO Change proposals for ISSUE-41 : Distributed Extensibility

On Mar 18, 2010, at 1:00 , Michael(tm) Smith wrote:

> Ian Hickson <ian@hixie.ch>, 2010-03-18 01:34 +0000:
> 
>> I have to be honest, I don't really understand the point of the "x" 
>> prefix. It seems unnecessary since people can use their own prefix just 
>> as easily.
> 
> The "x" prefix would make sense if the system for registering new
> prefixes is not open/user-editable -- e.g., for a case like the
> IANA language-subtag registry. But if the plan is for a registry
> system that is open/user-editable (using a wiki or whatever), then
> it does seem like the "x" prefix would not be needed.
> 


I think historically the IETF specs used the "x-" prefix precisely to emphasize that something was experimental, unregistered and hence nastily liable to collision, and so on.  It was intentional that only one prefix was used (rather than vendor specific), to emphasize the point.  The problem is, it didn't work, and in many places, x- prefixed names became the normal working practice, and you had to know about them if you wanted to interoperate;  but they could not be documented/registered since, by definition, they were in the experimental, unregistered part of the namespace.

David Singer
Multimedia and Software Standards, Apple Inc.

Received on Thursday, 18 March 2010 19:37:42 UTC