And Now for XAML Completely Different

//
// MarkupScript                                                  
// Author: Tom Englert
// Contact: mail@tom-englert.de
// Copyright (C) 2010 tom-englert.de
//

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Collections;
using System.Windows.Markup;

namespace MarkupScript
{
    /// <summary>
    /// Base class for all unary expressions.
    /// Unary expressions evaluate their value property.
    /// </summary>
    public abstract class UnaryExpression : Statement, IExpression
    {
        /// <summary>
        /// The expression to evaluate.
        /// </summary>
        [ConstructorArgument("value")]
        public IExpression Value { get; set; }

        /// <summary>
        /// The evaluator for the specific expression.
        /// </summary>
        private Func<object, object> evaluator;

        protected UnaryExpression(Func<object, object> evaluator)
        {
            this.evaluator = evaluator;
        }

        public override object OnEvaluate()
        {
            return evaluator(Value.Evaluate());
        }
    }

    public class Not : UnaryExpression, IStatement
    {
        public Not() : base(a => !ToBoolean(a)) { }
    }

    public class Negate : UnaryExpression
    {
        public Negate() : base(a => -ToDouble(a)) { }
    }

    public class Count : UnaryExpression
    {
        public Count() : base(a => GetCount(a)) { }

        private static object GetCount(object value)
        {
            IList list = value as IList;
            if (list != null)
            {
                return list.Count;
            }

            IEnumerable enumerable = value as IEnumerable;
            if (enumerable != null)
            {
                return enumerable.Cast<object>().Count();
            }

            return 0;
        }
    }

    public class Random : Statement, IStatement, IExpression
    {
        private static System.Random random = new System.Random();

        public double MinValue { get; set; }
        public double MaxValue { get; set; }

        public Random()
            : this(1.0)
        {
        }

        public Random(double maxValue)
        {
            this.MaxValue = maxValue;
        }

        public override object OnEvaluate()
        {
            return random.Next((int)MinValue, (int)MaxValue);
        }
    }
}