Predicate.cs

using Waher.Script;
using Waher.Script.Abstraction.Elements;
using Waher.Script.Exceptions;
using Waher.Script.Model;
 
namespace Waher.Content.Semantic.Functions
{
    public class Predicate : FunctionOneSemanticVariable
    {
        public Predicate(ScriptNode Argument, int Start, int Length, Expression Expression)
            : base(Argument, Start, Length, Expression)
        {
        }
 
        public override string FunctionName => nameof(Predicate);
 
        public override IElement EvaluateScalar(ISemanticElement Argument, Variables Variables)
        {
            if (Argument is ISemanticTriple Triple)
                return Triple.Predicate;
            else
                throw new ScriptRuntimeException("Semantic triple expected.", this);
        }
    }
}