gnu.prolog.vm
Class PrologCollectionIterator

java.lang.Object
  gnu.prolog.vm.BacktrackInfo
      gnu.prolog.vm.PrologCollectionIterator

public class PrologCollectionIterator
extends BacktrackInfo

Generic collection iterator which can be used by PrologCode implementations.

Author:

Michiel Hendriks

Field Summary

protected Term	destTerm The term to unify the value with
protected Iterator<?>	iterator The iterator it will go through
protected int	startUndoPosition The start undo position

Fields inherited from class gnu.prolog.vm.BacktrackInfo

codePosition, undoPosition

Constructor Summary

PrologCollectionIterator(Iterable<?> iterable, Term destination, int undoPosition)

PrologCollectionIterator(Iterator<?> iterable, Term destination, int undoPosition)

Method Summary

int	getUndoPosition()
int	nextSolution(Interpreter interpreter) Get the next value

Methods inherited from class gnu.prolog.vm.BacktrackInfo

undo

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

iterator

protected Iterator<?> iterator

The iterator it will go through

destTerm

protected Term destTerm

The term to unify the value with

startUndoPosition

protected int startUndoPosition

The start undo position

Constructor Detail

PrologCollectionIterator

public PrologCollectionIterator(Iterable<?> iterable,
                                Term destination,
                                int undoPosition)

Parameters:

iterable - The collection to iterate over

destination - The destination term

undoPosition - the value of interpreter.getUndoPosition();

PrologCollectionIterator

public PrologCollectionIterator(Iterator<?> iterable,
                                Term destination,
                                int undoPosition)

Parameters:

iterable - The collection to iterate over

destination - The destination term

undoPosition - the value of interpreter.getUndoPosition();

Method Detail

getUndoPosition

public int getUndoPosition()

Returns:

the startUndoPosition

nextSolution

public int nextSolution(Interpreter interpreter)
                 throws PrologException

Get the next value

Parameters:

interpreter -

Returns:

Throws:

PrologException