Package net.sf.saxon.expr

## Interface ContextMappingFunction

- All Known Implementing Classes:
    `AnalyzeMappingFunction`, `CompiledContextMappingFunction`, `ForEach`, `ForEachGroup`, `MergeInstr.MergeKeyMappingFunction`, `MultithreadedForEach`

      public interface ContextMappingFunction

  ContextMappingFunction is an interface that must be satisfied by an object passed to a ContextMappingIterator. It represents an object which, given an Item, can return a SequenceIterator that delivers a sequence of zero or more Items.

  This is a specialization of the more general MappingFunction class: it differs in that each item being processed becomes the context item while it is being processed.

- - ### Method Summary

    All Methods Instance Methods Abstract Methods
    Modifier and Type | Method | Description
    --- | --- | ---
    `SequenceIterator` | `map​(XPathContext context)` | Map one item to a sequence.

- - ### Method Detail

    - #### map

          SequenceIterator map​(XPathContext context)
                        throws XPathException

      Map one item to a sequence.
      Parameters:
        `context` - The processing context. The item to be mapped is the context item identified from this context: the values of position() and last() also relate to the set of items being mapped
      Returns:
        a SequenceIterator over the sequence of items that the supplied input item maps to
      Throws:
        `XPathException` - if a dynamic error is detected