Last.cs

using System.Threading.Tasks;
using Waher.Script.Abstraction.Elements;
using Waher.Script.Model;
using Waher.Script.Objects;
 
namespace Waher.Script.Functions.Vectors
{
    public class Last : FunctionOneVectorVariable, IIterativeEvaluation
    {
        public Last(ScriptNode Argument, int Start, int Length, Expression Expression)
            : base(Argument, Start, Length, Expression)
        {
        }
 
        public override string FunctionName => nameof(Last);
 
        protected override IElement EvaluateNonVector(IElement Argument, Variables Variables)
        {
            return Argument;
        }
 
        public override IElement EvaluateVector(IVector Argument, Variables Variables)
        {
            int c = Argument.Dimension;
            if (c == 0)
                return ObjectValue.Null;
            else
                return Argument.GetElement(c - 1);
        }
 
        public override IIterativeEvaluator CreateEvaluator()
        {
            return new LastEvaluator(this);
        }
    }
}