/// <summary> /// Gets the data type of the value. /// </summary> /// <param name="context">The evaluation context.</param> /// <returns>The data type descriptor.</returns> public IDataType GetType(EvaluationContext context) { return(EvaluationEngine.GetDataType(DataTypeValue)); }
/// <summary> /// This method overrides the ApplyBase method in order to provide extra validations /// required in the condition evaluation, for example the final return value should be a /// boolean value. /// </summary> /// <param name="context">The evaluation context instance.</param> /// <returns>The EvaluationValue with the results of the condition evaluation.</returns> public override EvaluationValue Evaluate(EvaluationContext context) { if (context == null) { throw new ArgumentNullException("context"); } context.Trace("Evaluating condition"); context.AddIndent(); try { // Iterate through the arguments, the IExpressionType is a mark interface foreach (IExpression arg in ApplyDefinition.Arguments) { if (arg is ApplyElement) { context.Trace("Apply within condition."); // There is a nested apply un this policy a new Apply will be created and also // evaluated. It's return value will be used as the processed argument. var childApply = new Apply((ApplyElement)arg); // Evaluate the Apply EvaluationValue retVal = childApply.Evaluate(context); return(retVal); } else if (arg is FunctionElementReadWrite) { throw new NotImplementedException("FunctionElement"); //TODO: } else if (arg is VariableReferenceElement) { var variableRef = arg as VariableReferenceElement; var variableDef = context.CurrentPolicy.VariableDefinition[variableRef.VariableId] as VariableDefinition; Debug.Assert(variableDef != null, "variableDef != null"); if (!variableDef.IsEvaluated) { return(variableDef.Evaluate(context)); } else { return(variableDef.Value); } } else if (arg is AttributeValueElementReadWrite) { // The AttributeValue does not need to be processed context.Trace("Attribute value {0}", arg.ToString()); var attributeValue = new AttributeValueElement(((AttributeValueElementReadWrite)arg).DataType, ((AttributeValueElementReadWrite)arg).Contents, ((AttributeValueElementReadWrite)arg).SchemaVersion); return(new EvaluationValue( attributeValue.GetTypedValue(attributeValue.GetType(context), 0), attributeValue.GetType(context))); } else if (arg is AttributeDesignatorBase) { // Returning an empty bag, since the condition is not supposed to work with a bag context.Trace("Processing attribute designator: {0}", arg.ToString()); var attrDes = (AttributeDesignatorBase)arg; var bag = new BagValue(EvaluationEngine.GetDataType(attrDes.DataType)); return(new EvaluationValue(bag, bag.GetType(context))); } else if (arg is AttributeSelectorElement) { // Returning an empty bag, since the condition is not supposed to work with a bag context.Trace("Attribute selector"); var attrSel = (AttributeSelectorElement)arg; var bag = new BagValue(EvaluationEngine.GetDataType(attrSel.DataType)); return(new EvaluationValue(bag, bag.GetType(context))); } } throw new NotSupportedException("internal error"); } finally { context.TraceContextValues(); context.RemoveIndent(); } }