using System;

using System.Reflection.Emit;

public class Program

{

    public static void Main()

    {

        int number = 42;

        int? notNumber = number;

        PrintFloat((float)number);

        PrintFloat((float)notNumber);

        PrintFloat(ToFloat1(number));

        PrintFloat(ToFloat2((ushort)number));

        PrintFloat(ToFloat3(notNumber));

        PrintFloat(ToFloat4(ref number));

    }

    private static void PrintFloat(float value)

    {

        Console.WriteLine(value.ToString());

    }

    private static Func<int, float> ToFloat1 = MakeCast<int, float>();

    private static Func<ushort, float> ToFloat2 = MakeCast<ushort, float>();

    private static Func<int?, float> ToFloat3 = MakeCast<int?, float>();

    private static RefFunc<int, float> ToFloat4 = MakeRefCast<int, float>();

    private static Func<T, V> MakeCast<T, V>()

    {

        var dm = new DynamicMethod("Cast", typeof(V), new[] { typeof(T) }, typeof(Program).Module);

        var il = dm.GetILGenerator();

        il.Emit(OpCodes.Ldarg_0);

        il.Emit(OpCodes.Ret);

        return (Func<T, V>)dm.CreateDelegate(typeof(Func<T, V>));

    }

    private static RefFunc<T, V> MakeRefCast<T, V>()

    {

        var dm = new DynamicMethod("RefCast", typeof(V), new[] { typeof(T).MakeByRefType() }, typeof(Program).Module);

        var il = dm.GetILGenerator();

        il.Emit(OpCodes.Ldarg_0);

        il.Emit(OpCodes.Ret);

        return (RefFunc<T, V>)dm.CreateDelegate(typeof(RefFunc<T, V>));

    }

    private delegate TResult RefFunc<T, TResult>(ref T argument);

}