IndexOrder.cs

using System;
using System.Collections.Generic;
using Waher.Script.Abstraction.Elements;
using Waher.Script.Exceptions;
using Waher.Script.Model;
 
namespace Waher.Script.Order
{
    public class IndexOrder : IComparer<IElement>
    {
        private readonly ScriptNode node;
        private readonly int index;
        private readonly int sign;
 
        public IndexOrder(ScriptNode Node, int Index, int Sign)
        {
            this.node = Node;
            this.index = Index;
            this.sign = Sign;
        }
 
        public int Compare(IElement x, IElement y)
        {
            if (x is IVector v1 && y is IVector v2)
            {
                IElement e1 = v1.GetElement(this.index);
                IElement e2 = v2.GetElement(this.index);
 
                return this.sign * ElementOrder.Compare(e1, e2, this.node);
            }
            else
                throw new ScriptRuntimeException("Elements in array must be vectors.", this.node);
        }
    }
}