public S Execute <S>(Expression expression)
{
var visitor = new ChangeSourceExpressionVisitor();
Expression newExpression = visitor.Visit(expression);
object result = _source.Provider.Execute(newExpression);
if (result != null && _source.ElementType == typeof(S))
{
result = (S)_wrappingMethodInfo.Invoke(null, new [] { result });
}
return((S)result);
}
private IEnumerable <T> BuildEnumerable()
{
if (_innerEnumerable == null)
{
lock (this) {
if (_innerEnumerable == null)
{
var visitor = new ChangeSourceExpressionVisitor();
Expression newExpression = visitor.Visit(_currentExpression);
var result = (IQueryable <T>)_source.Provider.CreateQuery(newExpression);
Verify.IsNotNull(result, "Failed to create an enumerator");
Thread.MemoryBarrier();
_innerEnumerable = result;
}
}
}
return(_innerEnumerable);
}