Fields.cs

using System;
using System.Collections.Generic;
using System.Reflection;
using System.Threading.Tasks;
using Waher.Script.Abstraction.Elements;
using Waher.Script.Model;
using Waher.Script.Objects;
using Waher.Script.Objects.Matrices;
using Waher.Script.Objects.VectorSpaces;
 
namespace Waher.Script.Functions.Runtime
{
    public class Fields : FunctionOneVariable
    {
        public Fields(ScriptNode Argument, int Start, int Length, Expression Expression)
            : base(Argument, Start, Length, Expression)
        {
        }
 
        public override string FunctionName => nameof(Fields);
 
        public override bool IsAsynchronous => true;
 
        public override IElement Evaluate(Variables Variables)
        {
            return this.EvaluateAsync(Variables).Result;
        }
 
        public override async Task<IElement> EvaluateAsync(Variables Variables)
        {
            IElement E = await this.Argument.EvaluateAsync(Variables);
            object Obj = E.AssociatedObjectValue;
            if (Obj is null)
                return ObjectValue.Null;
            
            List<IElement> Elements = new List<IElement>();
 
            if (Obj is Type T)
            {
                foreach (FieldInfo FI in T.GetRuntimeFields())
                {
                    if (FI.IsPublic)
                        Elements.Add(new StringValue(FI.Name));
                }
 
                return new ObjectVector(Elements);
            }
            else
            {
                T = Obj.GetType();
 
                foreach (FieldInfo FI in T.GetRuntimeFields())
                {
                    if (FI.IsPublic)
                    {
                        Elements.Add(new StringValue(FI.Name));
                        Elements.Add(Expression.Encapsulate(await WaitPossibleTask(FI.GetValue(Obj))));
                    }
                }
 
                ObjectMatrix M = new ObjectMatrix(Elements.Count / 2, 2, Elements)
                {
                    ColumnNames = new string[] { "Name", "Value" }
                };
 
                return M;
            }
        }
 
        public override IElement Evaluate(IElement Argument, Variables Variables)
        {
            return ObjectValue.Null;
        }
    }
}