intersect and except implementation

[tmuldner]

Does anybody know any implementation of XPaths that supports path
intersection and difference?

 

[Richard Tobin]

Does anybody know any implementation of XPaths that supports path
intersection and difference?

Exslt has functions for these operations.

-- Richard

 

[Joe Kesselman]

Websearch comes up with the "Kaysan method" for expressing these, by
leveraging the union operator and count to check for an element's
presence in the other set:

Intersection:
$set1[count(.|$set2)=count($set2)]

Symmetric difference:
( $set1[count(.|$set2)!=count($set2)]
| $set2[count(.|$set1)!=count($set1)] )

 

[Dimitre Novatchev]

As others have pointed out, the Kaysian method (originally used with XPath
1.0) has been around the last seven years.

Also, "intersect" and "except" are operators in the standard XPath 2.0
language, for which several implementations exist.

Embedded in XSLT 2.0: Saxon, Gestalt, Altova

Embedded in XQuery 1.0 -- many.


Cheers,
Dimitre Novatchev