Re: [xsl] Determine position in node sequence based on criteria

[Dimitre Novatchev <dnovatchev@xxxxxxxxx>]

> It would be much cleaner with a higher-order function, which you can write
> in XSLT/XPath 2.1:
>
> <xsl:function name="f:index-of" as="xs:integer*">
> <xsl:param name="sequence" as="item()*"/>
> <xsl:param name="test" as="function(item()) as xs:boolean"/>
> <xs:sequence select="for $i in 1 to count(sequence) return
> $i[$test($seq[$i])]"/>
> </xsl:function>
>
> then
>
> f:index-of(../c, function($c){matches($c, $regex)})
>


What would be the equivalent of this (possible even in XSLT 2.0) in
XSLT 2.1 / XPath 2.1:

    f:map(f:index-of($seq), $seq[f:someCondition(.)])

f:index-of($seq) is the partial application of f:index-of() on its
first argument.

What name has in F & O 1.1 the f:map() function?


--
Cheers,
Dimitre Novatchev
---------------------------------------
Truly great madness cannot be achieved without significant intelligence.
---------------------------------------
To invent, you need a good imagination and a pile of junk
-------------------------------------
Never fight an inanimate object
-------------------------------------
You've achieved success in your field when you don't know whether what
you're doing is work or play


On Wed, Jun 30, 2010 at 7:28 AM, Michael Kay <mike@xxxxxxxxxxxx> wrote:
>
>> Agreed. It seems like it would be real handy to have position() take
>> an argument:
>>
>> B position(../s[])
>>
>> and return the position of the matching items...
>
> The position of what item in what sequence?
>
>> or loosen the
>> restrictions on position() in a for expression, or have a different
>> function where you could get the position in a for expression:
>>
>> for $i in ../s
>> B if (...) then $i/position() else ()
>>
>>
>
> This all depends on maintaining more context, and we've arguably got too
> much context-sensitivity already, especially in XSLT.
>
> It would be much cleaner with a higher-order function, which you can write
> in XSLT/XPath 2.1:
>
> <xsl:function name="f:index-of" as="xs:integer*">
> <xsl:param name="sequence" as="item()*"/>
> <xsl:param name="test" as="function(item()) as xs:boolean"/>
> <xs:sequence select="for $i in 1 to count(sequence) return
> $i[$test($seq[$i])]"/>
> </xsl:function>
>
> then
>
> f:index-of(../c, function($c){matches($c, $regex)})
>
> Michael Kay
> Saxonica