[ietf-dkim] NEW ISSUE: remove [FWS] (was: SSP issues status)

[Charles Lindsey]

On Fri, 11 Jan 2008 07:42:49 -0000, Frank Ellermann  
<nobody at xyzzy.claranet.de> wrote:

> But SSP introduces unnecessary [FWS], where it
> is not required as separator, simplified:
>
> | tag = "dkim" [FWS] "=" [FWS] ( "x" / "y" )
>
> The "=" already separates name and value, you
> could as well write:
>
> | tag = "dkim=" ( "x" / "y" )

The world is full of protocols which ask you to write parameters of the  
form
    <name> "=" <value>
Some of them allow SP/WSP around the "=", some allow folding as well  
(maybe even comments), and some allow nothing. The biggest problem is for  
users to remember what they are/are not allowed to do in each case. Our  
first duty should be not to make that problem worse (supposing we can  
discern in which direction "worse" arises).

The nearest and best knwon precedent is MIME <parameter>s, which allow  
full CFWS around the "=" (though it requires rather careful reading of RFC  
822 to confirm that). Of course, nobody (FSVO "nobody") goes the whole hog  
by putting comments there, nor even spaces, but whitespace is quite  
common. Which suggests we should allow at least WSP*. I am happy to forget  
the full CFWS, and probably FWS too.

-- 
Charles H. Lindsey ---------At Home, doing my own thing------------------------
Tel: +44 161 436 6131                       
   Web: http://www.cs.man.ac.uk/~chl
Email: chl at clerew.man.ac.uk      Snail: 5 Clerewood Ave, CHEADLE, SK8 3JU, U.K.
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