/// <summary>
/// Orders the collection by applying given ordering.
/// </summary>
/// <param name="ordering">The ordering to use.</param>
/// <returns>Ordered collection.</returns>
/// <remarks>This overload allows for more intellisense-friendly way of specifying ordering.</remarks>
public QueryCollectionValue OrderBy(QueryOrdering ordering)
{
ExceptionUtilities.CheckArgumentNotNull(ordering, "ordering");
ExceptionUtilities.CheckCollectionNotEmpty(ordering.Selectors, "ordering.Selectors");
if (this.IsNull)
{
return(this);
}
IEnumerable <QueryValue> orderedElements = ordering.Apply(this.Elements.Cast <object>()).Cast <QueryValue>();
QueryError currentError = QueryError.Combine(this.EvaluationError, QueryError.GetErrorFromValues(orderedElements));
if (currentError != null)
{
return((QueryCollectionValue)this.Type.CreateErrorValue(currentError));
}
// if this collection contains duplicate order by key selectors
if (HasNondeterministicOrdering(ordering, orderedElements))
{
return(new QueryCollectionValue(this.Type, this.EvaluationStrategy, null, orderedElements, false));
}
else
{
return(new QueryCollectionValue(this.Type, this.EvaluationStrategy, null, orderedElements, true));
}
}
private QueryScalarValue EvaluateBinaryOperation(QueryScalarValue otherValue, QueryBinaryOperation operation)
{
ExceptionUtilities.CheckArgumentNotNull(otherValue, "otherValue");
var result = this.EvaluationStrategy.Evaluate(operation, this, otherValue);
var error = QueryError.Combine(this.EvaluationError, otherValue.EvaluationError);
if (error != null)
{
result.EvaluationError = error;
}
return(result);
}
/// <summary>
/// Applies the Take operation on the given collection.
/// </summary>
/// <param name="takeCount">How many elements to take.</param>
/// <returns>Collection with the applied Take operation.</returns>
public QueryCollectionValue Take(QueryScalarValue takeCount)
{
ExceptionUtilities.CheckArgumentNotNull(takeCount, "takeCount");
QueryError currentError = QueryError.Combine(this.EvaluationError, takeCount.EvaluationError);
if (currentError != null)
{
return((QueryCollectionValue)this.Type.CreateErrorValue(currentError));
}
IEnumerable <QueryValue> result = null;
if (!this.IsNull)
{
result = this.Elements.Take((int)takeCount.Value).ToList();
}
return(new QueryCollectionValue(this.Type, this.Type.EvaluationStrategy, QueryError.GetErrorFromValues(result), result, this.IsSorted));
}
/// <summary>
/// Applies the Skip operation on the given collection.
/// </summary>
/// <param name="skipCount">How many elements to skip.</param>
/// <returns>Collection with the applied Skip operation.</returns>
public QueryCollectionValue Skip(QueryScalarValue skipCount)
{
ExceptionUtilities.CheckArgumentNotNull(skipCount, "skipCount");
QueryError currentError = QueryError.Combine(this.EvaluationError, skipCount.EvaluationError);
if (currentError != null)
{
return((QueryCollectionValue)this.Type.CreateErrorValue(currentError));
}
IEnumerable <QueryValue> result = null;
if (!this.IsNull)
{
// perhaps this must be changed - moved to EvaluationStrategy
result = this.Elements.Skip((int)skipCount.Value);
}
return(new QueryCollectionValue(this.Type, this.Type.EvaluationStrategy, QueryError.GetErrorFromValues(result), result, this.IsSorted));
}
