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

Erik Wilde <dret@berkeley.edu> Fri, 26 April 2013 17:20 UTC

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Date: Fri, 26 Apr 2013 10:20:31 -0700
From: Erik Wilde <dret@berkeley.edu>
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Cc: Joe Gregorio <joe@bitworking.org>
Subject: Re: [apps-discuss] Question about URI template and expansion of an empty list
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hello joe.

thanks for the response!

On 2013-04-17 07:03 , Joe Gregorio wrote:
> On Mon, Apr 8, 2013 at 1:41 AM, Erik Wilde <dret@berkeley.edu> wrote:
>> https://github.com/dret/uritemplate-test/blob/master/spec-examples-by-section.json
>> (line 234) says it's "X", but i am really interested in the "why"
>> explanation as well. http://tools.ietf.org/html/rfc6570#section-3.2.5 says
>> that
> The answer is in the text you quote:
> "for each defined variable in the variable-list, append '.' to the
> result string and then perform variable expansion"
> The set of variables in the variable list is the empty set, so no '.'
> is appended.
> I agree that if this is confusing an addendum is in order.

... and just when i wanted to submit an erratum and searched for the 
best place where to put clarifying text, i ran into the last paragraph 
of http://tools.ietf.org/html/rfc6570#section-2.3 :

"A variable defined as a list value is considered undefined if the list 
contains zero members. A variable defined as an associative array of 
(name, value) pairs is considered undefined if the array contains zero 
members or if all member names in the array are associated with 
undefined values."

while still being a bit of an unintuitive definition for me, it seems as 
if this particular paragraph was never mentioned in previous 
discussions, and indeed clarifies that an empty array should be 
considered as an "undefined variable". for now, i'll assume that this 
settles things and will not file an erratum. but if people think 
(fracis? james?) that this still isn't good enough, then please speak up.

thanks and cheers,

dret.

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