Wildcard.cs

using System.Threading.Tasks;
using Waher.Script.Abstraction.Elements;
using Waher.Script.Model;
using Waher.Script.Objects;
 
namespace Waher.Script.Persistence.SQL
{
    public class Wildcard : ScriptLeafNode, IIterativeEvaluation
    {
        public Wildcard(int Start, int Length, Expression Expression)
            : base(Start, Length, Expression)
        {
        }
 
        public override IElement Evaluate(Variables Variables)
        {
            if (Variables is ObjectProperties Properties)
                return Expression.Encapsulate(Properties.Object);
            else
                return ObjectValue.Null;
        }
 
        public override Task<IElement> EvaluateAsync(Variables Variables)
        {
            return Task.FromResult(this.Evaluate(Variables));
        }
 
        public override bool Equals(object obj)
        {
            return obj is Wildcard;
        }
 
        public override int GetHashCode()
        {
            return "*".GetHashCode();
        }
 
        #region IIterativeEvaluation
 
        public bool CanEvaluateIteratively => true;
 
        public IIterativeEvaluator CreateEvaluator()
        {
            return new WildcardEvaluator(this);
        }
 
        #endregion
    }
}