Tamino XQuery User Guide - Software AG Documentation

Advanced Usage
module namespace tree="http://www.examples.com/tree"
declare function tree:depth($e as node()) as xs:integer
{
if (not($e/*))
then
1
else
max(for $c in $e/* return tree:depth($c)) + 1
}
declare function tree:siblings($a as element()) as element()*
{
for $x in $a/../*
where not($x is $a)
return $x
}
Before you can use the functions defined in a library module, you must store the module at a
special place to make it directly accessible to the XQuery processor. In Tamino, modules are stored
in the system collection ino:source. From a module definition, some meta data is derived to
provide access to module properties that are relevant for efficient lookup of modules and userdefined
functions. The meta data also simplifies querying module properties in order to generate
interface descriptions such as WSDL definitions.
Modules are stored as non-XML data in the ino:module doctype of the ino:source collection.
This way you can define modules using the _process command and remove them with _delete.
Alternatively, you can use the Tamino Interactive Interface.
Note that a library module must not contain variable declarations. Also, Tamino query pragmas
which are directives to the query processor are not allowed.
To use a module, you must import it with an import statement. Consider using the library of tree
functions:
import module namespace tree="http://www.examples.com/tree"
let $a := foo bar
return tree:siblings($a/a1)
This import statement imports the module with the target namespace http://www.examples.com/tree.
Note that you cannot import the same module more than once.
To check for existing modules, you can query the ino:source collection in the following way to
retrieve the non-XML data of all modules of a given namespace:
XQuery User Guide
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