Re: [apps-discuss] "X-" revisited

"Martin J. Dürst" <> Wed, 29 June 2011 07:28 UTC

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Date: Wed, 29 Jun 2011 16:27:39 +0900
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Organization: Aoyama Gakuin University
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Subject: Re: [apps-discuss] "X-" revisited
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Hello Peter,

I see:

    To preserve interoperability, newer implementations simply support
    the "X-" name forever, which means that the non-standard name becomes
    a de facto standard (thus obviating the need for segregation of the
    name spaces in the first place).  As one example, we can see this
    phenomenon at work in [RFC2068] (similar examples can be found in

I would want to propose a tiny change to the last phrase:

"similar examples" -> "a similar example"

(because it's only about one header, and there are no actual examples of 
the X- header in usage).

I'd also want to point out that I consider the
     X-Archived-At -> Archived-At
transition in many ways the 'ideal' success story for a X- prefix. But 
the success was due to some very special circumstances:

- When Archived-At was standardized, it was used only at two (very big)
   places, and these were willing and able to switch over extremely
- Usage is mainly by individuals, with "software update" possible by
   settings in MUAs and the like, which made the transition easy on
   the receiving side.
- There was somebody (me) who was willing to go through all the red
   tape, deal with people who claimed that it was totally useless, and
   so on.

Regards,   Martin.

On 2011/06/28 3:36, Peter Saint-Andre wrote:
> Based on comments received to date, I've published a heavily-revised
> version of the "X-" proposal:
> Further feedback is welcome!
> Peter