Re: Proposed EXPath module: resource collections

You wrote: 
I'm not aiming for portability at that level. If it's needed, it can be layered on top. For example, I can envisage a separate spec for SQL-collections that describes how to map collections to SQL databases, and what kind of properties such a collection exposes.
Very well, let us put portability out of scope. But still I have no clue how to map collections of resource descriptors to persistent artifacts without a scheme, if efficiency is important. 
 

     Michael Kay <mike@saxonica.com> schrieb am 9:37 Freitag, 20.Februar 2015:
   

 > 
> For me, there remains one major open question - how to express collection-specific models of resource descriptors, and I suggest the following requirements:
> 
> * an artifact which is accessible to the XQuery user
> * a format which is platform and XQuery processor independent
> 
> Advantages: the user can himself design and manage the collections (if appropriate API functions are provided); portability across XQuery processors.
> 
> How about a little XML vocabulary? Alternatives? Would you expect it to be hard to agree upon the details?
> 

Are you thinking here of some kind of concept of collection-type, where the properties of a collection depend on its collection-type, and there is some kind of schema for a collection-type to show what properties are available?

I was thinking of something much simpler, where each collection can have different properties, and indeed there might be different properties available for different resources within a collection (for example, directories within a directory have different property-sets than files within the same directory); users either know what properties to expect for a given collection URI, or find out what is available by using map:keys().

Michael Kay
Saxonica