Re: [apps-discuss] Question about URI template and expansion of an empty list

"Murray S. Kucherawy" <superuser@gmail.com> Mon, 08 April 2013 20:40 UTC

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Date: Mon, 08 Apr 2013 13:40:11 -0700
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From: "Murray S. Kucherawy" <superuser@gmail.com>
To: James M Snell <jasnell@gmail.com>
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Cc: IETF Apps Discuss <apps-discuss@ietf.org>, Joe Gregorio <joe@bitworking.org>
Subject: Re: [apps-discuss] Question about URI template and expansion of an empty list
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On Mon, Apr 8, 2013 at 7:50 AM, James M Snell <jasnell@gmail.com> wrote:

> "empty_keys" is not defined explicitly as an empty associative array.
> The only definition given for "empty_keys" in section 3.2 is
> "empty_keys := []" which is semantically and structurally identical to
> an empty list. So to amend your rules, we have:
>
> - an undefined value produces "X"
> - a defined-but-empty string produces "X."
> - a defined-but-empty list/associative-array produces "X"


Everywhere else in the document refers to a list as (value[, value[,
...]]).  So it seems to me "()" is the empty list, while "[]" is not.