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Re: Conditional Logic . . . what am I missing?

From: Christopher.R.Ball <christopher.r.ball@gmail.com>
Date: Tue, 01 May 2012 19:57:47 -0400
Message-ID: <4FA0787B.9070203@gmail.com>
To: Romain Deltour <rdeltour@gmail.com>
CC: xproc-dev@w3.org
Thanks for the clarification.

But then could you help me understand the purpose of @use-when? I am not 
getting the point of a seemingly conditional attribute that "must 
contain an XPath expression that can be evaluated statically"?

Christopher

On 5/1/2012 6:41 PM, Romain Deltour wrote:
> I don't think you're overlooking something. The p:choose with an identity in the otherwise branch is a common pattern.
>
> Romain.
>
> On 1 mai 2012, at 22:51, Christopher.R.Ball wrote:
>
>> I need to conditionally include an element in a pipeline and was rather surprised that my only option is to use<p:choose>.
>>
>> I would have thought I should be able to use 'use-when' but that seems to only take static values (which makes me wonder about what it is for).
>>
>> So I am having to use this:
>>
>>    <p:choose>
>>    <p:when test="$informative-matches = 0">
>>    <p:insert match="entity/other-searches" position="last-child">
>>    <p:input port="insertion" select="/entity/music-search"/>
>>    </p:insert>
>>    </p:when>
>>    <p:otherwise>
>>    <p:identity/>
>>    </p:otherwise>
>>    </p:choose>
>>
>>
>> When all I really want is this:
>>
>>
>>    <p:insert match="entity/other-searches" position="last-child"
>>    use-when"$informative-matches = 0">
>>    <p:input port="insertion" select="/entity/music-search"/>
>>    </p:insert>
>>
>> Hopefully, I am overlooking something obvious ;)
>>
>> Regards,
>>
>> Christopher
>>
Received on Tuesday, 1 May 2012 23:58:26 GMT

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