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using System;
using System.Linq.Expressions;
using System.Diagnostics;
using System.Threading;
 
namespace ConsoleApplication
{
    class Foo
    {
        public int Baz { get; set; }
 
    }
 
    class Program
    {
        static void Main(string[] args)
        {
            // Process.GetCurrentProcess().PriorityClass = ProcessPriorityClass.High;
 
            const int cycles = 10000;
 
            dynamic lambda;
            Func<object, bool> lambda2;
            Delegate lambda3;
            Func<Foo, bool> lambda4;
 
            Type theType = typeof(Foo);
            Expression right = Expression.Constant(1);
 
            {
                ParameterExpression pe = Expression.Parameter(theType, "f");
                Expression left = Expression.Property(pe, theType.GetProperty("Baz"));
                Expression expr = Expression.Equal(left, right);
                // This works fine but uses a hard-coded type, which I won't know until runtime:
                lambda = Expression.Lambda(expr, new ParameterExpression[] { pe }).Compile();
                lambda3 = Expression.Lambda(expr, new ParameterExpression[] { pe }).Compile(); ;
            }
 
            {
                ParameterExpression pe = Expression.Parameter(typeof(object), "f");
                Expression pe2 = Expression.Convert(pe, theType);
                Expression left = Expression.Property(pe2, theType.GetProperty("Baz"));
                Expression expr = Expression.Equal(left, right);
                lambda2 = Expression.Lambda<Func<object, bool>>(expr, new ParameterExpression[] { pe }).Compile();
            }
 
            {
                ParameterExpression pe = Expression.Parameter(typeof(Foo), "f");
                Expression pe2 = Expression.Convert(pe, theType);
                Expression left = Expression.Property(pe2, theType.GetProperty("Baz"));
                Expression expr = Expression.Equal(left, right);
                lambda4 = Expression.Lambda<Func<Foo, bool>>(expr, new ParameterExpression[] { pe }).Compile();
            }
 
            var t = new Foo { Baz = 1 };
 
            for (int i = 0; i < 1000; i++)
            {
                lambda(t);
                lambda2(t);
                lambda3.DynamicInvoke(t);
                lambda4(t);
            }
 
            Thread.Sleep(1000);
 
            Stopwatch sw = Stopwatch.StartNew();
 
            for (int i = 0; i < cycles; i++)
            {
                if (!lambda(t))
                {
                    throw new Exception();
                }
            }
 
            sw.Stop();
 
            Stopwatch sw2 = Stopwatch.StartNew();
 
            for (int i = 0; i < cycles; i++)
            {
                if (!lambda2(t))
                {
                    throw new Exception();
                }
            }
 
            sw2.Stop();
 
            Stopwatch sw3 = Stopwatch.StartNew();
 
            for (int i = 0; i < cycles; i++)
            {
                if (!(bool)lambda3.DynamicInvoke(t))
                {
                    throw new Exception();
                }
            }
 
            sw3.Stop();
 
            Stopwatch sw4 = Stopwatch.StartNew();
 
            for (int i = 0; i < cycles; i++)
            {
                if (!lambda4(t))
                {
                    throw new Exception();
                }
            }
 
            sw4.Stop();
 
            Console.WriteLine("{0,12} dynamic", sw.ElapsedTicks);
            Console.WriteLine("{0,12} Func<object, bool>", sw2.ElapsedTicks);
            Console.WriteLine("{0,12} Delegate.DynamicInvoke", sw3.ElapsedTicks);
            Console.WriteLine("{0,12} Func<Foo, bool>", sw4.ElapsedTicks);
        }
    }
}
 

prog.cs(22,13): error CS1980: Dynamic keyword requires `System.Runtime.CompilerServices.DynamicAttribute' to be defined. Are you missing System.Core.dll assembly reference?
prog.cs(59,17): error CS0518: The predefined type `Microsoft.CSharp.RuntimeBinder.Binder' is not defined or imported
prog.cs(59,17): error CS0518: The predefined type `System.Runtime.CompilerServices.CallSite' is not defined or imported
prog.cs(59,17): error CS0518: The predefined type `System.Runtime.CompilerServices.CallSite' is not defined or imported
prog.cs(59,17): error CS1969: Dynamic operation cannot be compiled without `Microsoft.CSharp.dll' assembly reference
prog.cs(71,22): error CS0518: The predefined type `Microsoft.CSharp.RuntimeBinder.Binder' is not defined or imported
prog.cs(71,22): error CS0518: The predefined type `System.Runtime.CompilerServices.CallSite' is not defined or imported
prog.cs(71,22): error CS0518: The predefined type `System.Runtime.CompilerServices.CallSite' is not defined or imported
prog.cs(71,22): error CS1969: Dynamic operation cannot be compiled without `Microsoft.CSharp.dll' assembly reference
prog.cs(71,21): error CS0518: The predefined type `Microsoft.CSharp.RuntimeBinder.Binder' is not defined or imported
prog.cs(71,21): error CS0518: The predefined type `System.Runtime.CompilerServices.CallSite' is not defined or imported
prog.cs(71,21): error CS0518: The predefined type `System.Runtime.CompilerServices.CallSite' is not defined or imported
prog.cs(71,21): error CS1969: Dynamic operation cannot be compiled without `Microsoft.CSharp.dll' assembly reference
prog.cs(71,21): error CS0518: The predefined type `Microsoft.CSharp.RuntimeBinder.Binder' is not defined or imported
prog.cs(71,21): error CS0518: The predefined type `System.Runtime.CompilerServices.CallSite' is not defined or imported
prog.cs(71,21): error CS0518: The predefined type `System.Runtime.CompilerServices.CallSite' is not defined or imported
prog.cs(71,21): error CS1969: Dynamic operation cannot be compiled without `Microsoft.CSharp.dll' assembly reference
Compilation failed: 17 error(s), 0 warnings

Standard output is empty