public override XQueryNodeIterator Clone()
{
BufferedNodeIterator clone = new BufferedNodeIterator();
clone.src = src;
clone.buffer = buffer;
return clone;
}
private Task<Object> BeginMoveNext(IContextProvider provider, object[] args, MemoryPool pool, XPathItem curr, Integer index)
{
object value;
if (curr.IsNode)
value = curr.Clone();
else
value = curr.TypedValue;
if (m_varType != XQuerySequenceType.Item && m_convert)
{
if (m_varType.IsNode && !Core.InstanceOf(QueryContext.Engine, value, m_varType))
throw new XQueryException(Properties.Resources.XPTY0004,
new XQuerySequenceType(curr.XmlType.TypeCode), m_varType);
value = XQueryConvert.TreatValueAs(value, m_varType);
if (m_varType.Cardinality == XmlTypeCardinality.ZeroOrMore ||
m_varType.Cardinality == XmlTypeCardinality.OneOrMore)
value = XQueryNodeIterator.Create(value);
}
pool.SetData(m_value, value);
if (m_pos != null)
pool.SetData(m_posValue, index);
if (m_conditionExpr == null ||
Core.BooleanValue(QueryContext.Engine.Apply(null, null, ConditionExpr, args, m_conditionExpr, pool)))
{
MemoryPool taskPool = pool.Clone();
return Task<Object>.Factory.StartNew(() =>
{
object res = m_bodyExpr.Execute(provider, args, taskPool);
XQueryNodeIterator iter = res as XQueryNodeIterator;
if (iter != null)
{
BufferedNodeIterator resIter = new BufferedNodeIterator(iter, false);
resIter.Fill();
return resIter;
}
return res;
}, QueryContext.Token);
}
return null;
}
