XQuery嵌套循环的自动增量辅助索引var（w。动态计数） [英] Autoincremental auxiliar index var for XQuery nested loops (w. dynamical count)

问题描述

我想要一个解决方案，如何在xQuery中保存一个真正的循环计数器作为Java，而不是我的特定简化演示的解决方法。我知道在xQuery 3.0中有一个用于FLOWR结构的计数保留字，但是它的无用的前Saxon 9.something。这是我的例子。

I want a solution for udnerstanding how to hold a real loop counter as Java in xQuery, not a workaround for my particular simplified demo. I know in xQuery 3.0 there is a count reserved word for FLOWR structures but its useless pre-Saxon 9.something. Here my example.

     for $elem at $x in /Data/* return element Elem {       
            attribute Name   {concat('_',$x,'.',name($elem))},      
            (: ...10 lines of code... :)        
            for $subelem at $y in $elem/*       
            (: ...5 lets... :)      
            return element SubElemen {
               attribute Name {concat('_',$x,'.',$y,'_',name($subelement))},
               (...20 lines of other attrs and elements ...)
           for $subsubelem at $z in $subElem/SubSubElement
               let $absIterIndex := 'THIS IS WHAT IM LOOKING'
               let $subSubElemName := concat('_',$absIterIndex,'_',name($subElem))
            return
                                 element SubSubElem {
                 attribute Name {$subsubelem}, 
                   (..100 lines more playing with $x, $y, $absIterIndex, all lets for that iteration, attributes depending on them...)

输出是这样的（真实数据隐藏和简化）

The output is something like this (real data hidden and simplified)

 <Elem Name="_1.Name">
      <SubElem Name="_1.1_Name">
           <SubSubElem Name="_1.First"/>
           <SubSubElem Name="_2.Second"/>
           <SubSubElem Name="_3.Third"/>
      </SubElem Name="_1.1_Name">
      <SubElem Name="_1.2_Name">
           <SubSubElem Name="_4.Fourth"/>
           <SubSubElem Name="_5.Fifth"/>
           <SubSubElem Name="_6.Sixth"/>
           <SubSubElem Name="_7.Seventh"/>
      </SubElem Name="_1.1_Name">
  <Elem Name="_2.Name">
      <SubElem Name="_2.1_Name">
           <SubSubElem Name="_8.Eighth"/>
           <SubSubElem Name="_9.Ninth"/>
           <SubSubElem Name="_10.Tenth"/>
           <SubSubElem Name="_11.Eleventh"/>
      </SubElem Name="_2.1_Name">
      <SubElem Name="_2.2_Name"/>
  </Elem Name="_2.Name">
  <Elem Name="_3.Name">
      <SubElem Name="_3.1_Name">
           <SubSubElem Name="_12.Twelven"/>
      </SubElem Name="_3.1_Name">
      <SubElem Name="_3.2_Name"/>
  </Elem Name="_3.Name">     

这是上一个问题的扩展 XQuery嵌套循环的Autoincremental辅助索引变量，我接受了xQuery 3.0计数器的解决方案，然后提出了另一种选择手动完成它。但是我知道我认为这种观点是不同的，更具体，并且有一个新的例子。如果您认为应删除它，请告诉我。

This is a extension of a previous question Autoincremental auxiliar index var for XQuery nested loops, which I accepted the solution for the xQuery 3.0 counter, and then propose an alternative for manually doing it. But know i think the perspective is different and more concrete, and with a new example. If you think it should be deleted just tell it to me.

推荐答案

新问题 - 新答案。

New question - new answer.

但原则保持不变：首先产生无编号的结果，然后应用编号。这可能需要重写结果。

But the principle remains the same: produce an unnumbered result first, then apply the numbering. This may require rewriting the result.

插入代码而不是下面的XML注释。

Insert your code instead of the XML comment below.

declare function local:renumber($number, $string)
{
  replace($string, 'THIS IS WHAT IM LOOKING', string($number))
};

declare function local:renumber($subSubElems, $number, $nodes)
{
  for $node in $nodes
  return
    typeswitch ($node)
    case attribute()              return attribute {node-name($node)} {local:renumber($number, $node)}
    case processing-instruction() return processing-instruction {name($node)} {local:renumber($number, $node)}
    case comment()                return comment {local:renumber($number, $node)}
    case text()                   return text {local:renumber($number, $node)}
    default (: element() :) return
      element {node-name($node)}
      {
        local:renumber
        (
          $subSubElems, 
          if ($subSubElems[. is $node]) then count($subSubElems[. << $node]) + 1 else $number, 
          ($node/@*, $node/node())
        )
      }
};

let $result := <result>{<!-- your code here -->}</result>
return local:renumber($result//SubSubElem, 0, $result/node())

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