VectorForEachDefinition.cs

using System.Collections;
using System.Collections.Generic;
using System.Threading.Tasks;
using Waher.Script.Abstraction.Elements;
using Waher.Script.Model;
using Waher.Script.Operators.Conditional;
 
namespace Waher.Script.Operators.Vectors
{
    public class VectorForEachDefinition : BinaryOperator
    {
        private readonly string variableName;
 
        public VectorForEachDefinition(ForEach Elements, int Start, int Length, Expression Expression)
            : base(Elements.LeftOperand, Elements.RightOperand, Start, Length, Expression)
        {
            this.variableName = Elements.VariableName;
        }
 
        public string VariableName => this.variableName;
 
        public override IElement Evaluate(Variables Variables)
        {
            IElement S = this.left.Evaluate(Variables);
            LinkedList<IElement> Elements2 = new LinkedList<IElement>();
            
            if (!(S is ICollection<IElement> Elements))
            {
                if (S is IVector Vector)
                    Elements = Vector.VectorElements;
                else if (!S.IsScalar)
                    Elements = S.ChildElements;
                else if (S.AssociatedObjectValue is IEnumerable Enumerable)
                {
                    IEnumerator e = Enumerable.GetEnumerator();
 
                    while (e.MoveNext())
                    {
                        Variables[this.variableName] = e.Current;
                        Elements2.AddLast(this.right.Evaluate(Variables));
                    }
 
                    return this.Encapsulate(Elements2);
                }
                else
                    Elements = new IElement[] { S };
            }
 
            foreach (IElement Element in Elements)
            {
                Variables[this.variableName] = Element;
                Elements2.AddLast(this.right.Evaluate(Variables));
            }
 
            return this.Encapsulate(Elements2);
        }
 
        public override async Task<IElement> EvaluateAsync(Variables Variables)
        {
            if (!this.isAsync)
                return this.Evaluate(Variables);
 
            IElement S = await this.left.EvaluateAsync(Variables);
            LinkedList<IElement> Elements2 = new LinkedList<IElement>();
 
            if (!(S is ICollection<IElement> Elements))
            {
                if (S is IVector Vector)
                    Elements = Vector.VectorElements;
                else if (!S.IsScalar)
                    Elements = S.ChildElements;
                else if (S.AssociatedObjectValue is IEnumerable Enumerable)
                {
                    IEnumerator e = Enumerable.GetEnumerator();
 
                    while (e.MoveNext())
                    {
                        Variables[this.variableName] = e.Current;
                        Elements2.AddLast(await this.right.EvaluateAsync(Variables));
                    }
 
                    return this.Encapsulate(Elements2);
                }
                else
                    Elements = new IElement[] { S };
            }
 
            foreach (IElement Element in Elements)
            {
                Variables[this.variableName] = Element;
                Elements2.AddLast(await this.right.EvaluateAsync(Variables));
            }
 
            return this.Encapsulate(Elements2);
        }
 
        protected virtual IElement Encapsulate(LinkedList<IElement> Elements)
        {
            return VectorDefinition.Encapsulate(Elements, true, this);
        }
 
    }
}