/// <summary>
/// Calculates the Numeric Value of this Expression as evaluated for a given Binding.
/// </summary>
/// <param name="context">Evaluation Context.</param>
/// <param name="bindingID">Binding ID.</param>
/// <returns></returns>
public override IValuedNode Evaluate(SparqlEvaluationContext context, int bindingID)
{
IValuedNode a = _leftExpr.Evaluate(context, bindingID);
IValuedNode b = _rightExpr.Evaluate(context, bindingID);
IValuedNode[] inputs = new IValuedNode[] { a, b };
ISparqlOperator op = null;
if (SparqlOperators.TryGetOperator(SparqlOperatorType.Subtract, out op, inputs))
{
return(op.Apply(inputs));
}
else
{
throw new RdfQueryException("Cannot apply addition to the given inputs");
}
// if (a == null || b == null) throw new RdfQueryException("Cannot apply subtraction when one/both arguments are null");
// SparqlNumericType type = (SparqlNumericType)Math.Max((int)a.NumericType, (int)b.NumericType);
// switch (type)
// {
// case SparqlNumericType.Integer:
// return new LongNode(null, a.AsInteger() - b.AsInteger());
// case SparqlNumericType.Decimal:
// return new DecimalNode(null, a.AsDecimal() - b.AsDecimal());
// case SparqlNumericType.Float:
// return new FloatNode(null, a.AsFloat() - b.AsFloat());
// case SparqlNumericType.Double:
// return new DoubleNode(null, a.AsDouble() - b.AsDouble());
// default:
// throw new RdfQueryException("Cannot evalute an Arithmetic Expression when the Numeric Type of the expression cannot be determined");
// }
}
private void TestApplication(SparqlOperatorType opType, IEnumerable <IValuedNode> ns, IValuedNode expected, bool shouldFail)
{
ISparqlOperator op = null;
if (SparqlOperators.TryGetOperator(opType, out op, ns.ToArray()))
{
IValuedNode actual;
try
{
actual = op.Apply(ns.ToArray());
}
catch (Exception)
{
if (shouldFail)
{
return;
}
throw;
}
Assert.Equal(expected, actual);
}
else
{
Assert.True(shouldFail, "Expected to be able to select an operator to apply to the inputs");
}
}
private void TestLookup(SparqlOperatorType opType, Type returnedOpInstanceType, IEnumerable <IValuedNode> ns, bool opExists)
{
ISparqlOperator op = null;
if (SparqlOperators.TryGetOperator(opType, out op, ns.ToArray()))
{
Assert.True(opExists, "Operator returned when no operator was expected for the given inputs");
Assert.Equal(returnedOpInstanceType, op.GetType());
}
else
{
Assert.False(opExists, "No Operator returned when an operator was expected for the given inputs");
}
}
/// <summary>
/// Calculates the Numeric Value of this Expression as evaluated for a given Binding
/// </summary>
/// <param name="context">Evaluation Context</param>
/// <param name="bindingID">Binding ID</param>
/// <returns></returns>
public override IValuedNode Evaluate(SparqlEvaluationContext context, int bindingID)
{
IValuedNode a = this._leftExpr.Evaluate(context, bindingID);
IValuedNode b = this._rightExpr.Evaluate(context, bindingID);
IValuedNode[] inputs = new IValuedNode[] { a, b };
ISparqlOperator op = null;
if (SparqlOperators.TryGetOperator(SparqlOperatorType.Divide, out op, inputs))
{
return(op.Apply(inputs));
}
else
{
throw new RdfQueryException("Cannot apply division to the given inputs");
}
}
public void ConfigurationAutoOperators1()
{
try
{
String data = @"@prefix dnr: <http://www.dotnetrdf.org/configuration#> .
_:a a dnr:SparqlOperator ;
dnr:type """ + typeof(MockSparqlOperator).AssemblyQualifiedName + @""" .";
Graph g = new Graph();
g.LoadFromString(data);
ConfigurationLoader.AutoConfigureSparqlOperators(g);
ISparqlOperator op;
SparqlOperators.TryGetOperator(SparqlOperatorType.Add, out op, null);
Assert.AreEqual(typeof(MockSparqlOperator), op.GetType());
SparqlOperators.RemoveOperator(op);
}
finally
{
SparqlOperators.Reset();
}
}
