Re: [xri] XRD priority attributes

[Victor Grey <victor@idcommons.org>]

Perfect. Umm... well to be perfectly nit-pickingly clear, perhaps 2. 
should be:
"If an element has no priority attribute, its priority attribute value 
is considered to be null."
=vg

Drummond Reed wrote:
> Victor,
>
> In response to your suggestion below, following is the proposed new 
> text
> regarding priority attribute processing in Working Draft 10 (underway).
> Please do look this over and let me know if captures your intent.
>
> =Drummond
>
> ***BEGIN EXCERPT***
>
> The processing rules for the priority attribute are standard for all
> services in the XRI resolution framework. They apply whenever there is 
> more
> than one instance of the desired element type in an XRD (if there is 
> only
> one instance, the priority attribute is ignored). The rules are:
>
> 1.	The client SHOULD select the element instance with the lowest
> numeric value of the priority attribute. For example, an element with
> priority attribute value of "10" should be selected before an element 
> with a
> priority attribute value of "11", and an element with priority 
> attribute
> value of "11" should be selected before an element with a priority 
> attribute
> value of "15". Zero is the highest priority attribute value. Null is 
> the
> lowest priority attribute value.
>
> 2.	If an element has no priority attribute, its value is considered
> null.
>
> 3.	If two or more instances of the same element type have identical
> priority attribute values (including the null value), the client SHOULD
> select one of the instances at random.
>
> 4.	An element selected according to these rules is referred to as "the
> highest priority element". If this element is subsequently 
> disqualified from
> the set of matching elements, the next element selected according to 
> these
> rules is referred to as "the next highest priority element". If a 
> protocol
> operation specifying selection of the highest priority element fails, 
> the
> client SHOULD attempt to select the next highest priority element 
> unless
> otherwise specified. This process SHOULD be continued for all other 
> element
> instances until success is achieved or all instances are exhausted.
>
> *** END ***