net.sf.saxon.expr
Interface MappingFunction<F extends Item,T extends Item>

All Known Implementing Classes:

Atomizer.AtomizingFunction, ForExpression.MappingAction, ForSequenceMappingAction, KeyMappingFunction

public interface MappingFunction<F extends Item,T extends Item>

MappingFunction is an interface that must be satisfied by an object passed to a MappingIterator. It represents an object which, given an Item, can return a SequenceIterator that delivers a sequence of zero or more Items. This is a generic interface, where F represents the type of the input to the mapping function, and T represents the type of the result

Method Summary

SequenceIterator<T>

map(F item) Map one item to a sequence.

Method Detail

map

SequenceIterator<T> map(F item)
                                     throws XPathException

Map one item to a sequence.

Parameters:

item - The item to be mapped.

Returns:

one of the following: (a) a SequenceIterator over the sequence of items that the supplied input item maps to, or (b) null if it maps to an empty sequence.

Throws:

XPathException - if a dynamic error occurs