protected override Expression VisitNew(NewExpression node)
{
var newNode = (NewExpression)base.VisitNew(node);
if (newNode.Type.IsGenericType
&& newNode.Type.GetGenericTypeDefinition() == typeof(HashSet<>)
&& newNode.Arguments.Count == 1
&& newNode.Arguments[0] is AccumulatorExpression
&& ((AccumulatorExpression)newNode.Arguments[0]).AccumulatorType == AccumulatorType.Push)
{
Guid correlationId = Guid.Empty;
if (_groupMap == null || TryGetCorrelatedGroup(node.Arguments[0], out correlationId))
{
Expression accumulator = new AccumulatorExpression(
newNode.Type,
AccumulatorType.AddToSet,
((AccumulatorExpression)newNode.Arguments[0]).Argument);
if (_groupMap != null)
{
accumulator = new CorrelatedAccumulatorExpression(
correlationId,
(AccumulatorExpression)accumulator);
}
return accumulator;
}
}
return newNode;
}
protected internal override Expression VisitCorrelatedAccumulator(CorrelatedAccumulatorExpression node)
{
Expression mapped;
if (_map.TryGetValue(node, out mapped))
{
return mapped;
}
return base.VisitCorrelatedAccumulator(node);
}
protected internal virtual Expression VisitCorrelatedAccumulator(CorrelatedAccumulatorExpression node)
{
return(node.Update(VisitAndConvert <AccumulatorExpression>(node.Accumulator, "VisitCorrelatedAccumulator")));
}
protected internal virtual Expression VisitCorrelatedAccumulator(CorrelatedAccumulatorExpression node)
{
return node.Update(VisitAndConvert<AccumulatorExpression>(node.Accumulator, "VisitCorrelatedAccumulator"));
}
protected internal override Expression VisitCorrelatedAccumulator(CorrelatedAccumulatorExpression node)
{
_accumulators.Add(node);
// there could be nested accumulators we need to get...
return base.VisitCorrelatedAccumulator(node);
}
protected internal override Expression VisitCorrelatedAccumulator(CorrelatedAccumulatorExpression node)
{
if(node.CorrelationId == _correlationId)
{
return Visit(node.Accumulator);
}
return base.VisitCorrelatedAccumulator(node);
}
private bool TryBindAccumulatorExpression(MethodCallExpression node, out Expression accumulator)
{
AccumulatorType accumulatorType;
if (TryGetAccumulatorType(node.Method.Name, out accumulatorType))
{
Guid correlationId = Guid.Empty;
if (_groupMap == null || TryGetCorrelatedGroup(node.Arguments[0], out correlationId))
{
accumulator = new AccumulatorExpression(node.Type,
accumulatorType,
GetAccumulatorArgument(node));
if (_groupMap != null)
{
accumulator = new CorrelatedAccumulatorExpression(
correlationId,
(AccumulatorExpression)accumulator);
}
return true;
}
}
accumulator = null;
return false;
}
