XQDDF access-keys($index) function

[William Candillon]

XQDDF lacks a function for reading index keys from an index.

[Matthias Brantner (matthias-brantner)]

I suggest to name the function keys($name)

[Matthias Brantner (matthias-brantner)]

Also, I suggest to return values of the following structure:

 <key xmlns="index module namespace">
   <attribute value="key1_value"/>
   <attribute value="key2_value"/>
   <attribute value="key3_value"/>
 </key>

This is consistent with the unordered-map module.

[William Candillon (wcandillon)]

I'm confused about this following structure.
Where is the type information about the index key?
How to you handle multiple index keys?
Should it be something like:
<index>
  <keys>
     <key value type />
   </keys>
   ...
</index>

We also need to find an expression for a key that evaluates to empty-sequence()