protected internal virtual Expression VisitArrayIndex(ArrayIndexExpression node)
{
return(node.Update(
Visit(node.Array),
Visit(node.Index),
node.Original));
}
protected internal override Expression VisitArrayIndex(ArrayIndexExpression node)
{
var field = Visit(node.Array) as IFieldExpression;
if (field != null)
{
var constantIndex = node.Index as ConstantExpression;
if (constantIndex == null)
{
throw new NotSupportedException($"Only a constant index is supported in the expression {node}.");
}
var index = constantIndex.Value.ToString();
if (index == "-1")
{
// We've treated -1 as meaning $ operator. We can't break this now,
// so, specifically when we are flattening fields names, this is
// how we'll continue to treat -1.
index = "$";
}
return new FieldExpression(
field.AppendFieldName(index),
node.Serializer);
}
return node;
}
protected internal virtual Expression VisitArrayIndex(ArrayIndexExpression node)
{
return node.Update(
Visit(node.Array),
Visit(node.Index),
node.Original);
}
private BsonValue TranslateArrayIndex(ArrayIndexExpression node)
{
return new BsonDocument("$arrayElemAt", new BsonArray
{
TranslateValue(node.Array),
TranslateValue(node.Index)
});
}