Re: empty lists?, was: Last Call: <draft-ietf-httpbis-header-structure-18.txt> (Structured Field Values for HTTP) to Proposed Standard

Benjamin Kaduk <bkaduk@akamai.com> Mon, 18 May 2020 18:28 UTC

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Date: Mon, 18 May 2020 11:27:46 -0700
From: Benjamin Kaduk <bkaduk@akamai.com>
To: Julian Reschke <julian.reschke@gmx.de>
Cc: last-call@ietf.org, httpbis-chairs@ietf.org, ietf-http-wg@w3.org, barryleiba@gmail.com, draft-ietf-httpbis-header-structure@ietf.org
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Subject: Re: empty lists?, was: Last Call: <draft-ietf-httpbis-header-structure-18.txt> (Structured Field Values for HTTP) to Proposed Standard
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On Mon, May 18, 2020 at 03:06:02PM +0200, Julian Reschke wrote:
> On 13.05.2020 05:59, Julian Reschke wrote:
> > ...
> 
> Another late commment...
> 
> <https://greenbytes.de/tech/webdav/draft-ietf-httpbis-header-structure-18.html#rfc.section.3.1>:
> 
> > 3.1. Lists
> > 
> > Lists are arrays of zero or more members, each of which can be an Item (Section 3.3) or an Inner List (Section 3.1.1), both of which can be Parameterized (Section 3.1.2).
> > 
> > The ABNF for Lists in HTTP fields is:
> > 
> > sh-list       = list-member *( *SP "," *SP list-member )
> > list-member   = sh-item / inner-list
> 
> 
> So the prose says zero elements are allowed, but the ABNF actually
> requires one element.
> 
> One of these is incorrect...

You saw

   An empty List is denoted by not serializing the field at all.

right?

-Ben