using System;

using System.Collections.Generic;

using System.Linq;

​

​

namespace Example

{    

    public class Demo

    {

​

            Func<T, R> Compose0<T, U, R>(Func<T, U> f, Func<U, R> g) =>

             (T x) => g(f(x));

​

            Func<T, U, R2> Compose<T, U, R1, R2>(Func<T, U, R1> f, Func<R1, R2> g) =>

                (T x, U y) => g(f(x, y));

​

            Func<T, U, V, R2> Compose1<T, U, V, R1, R2>(Func<T, U, V, R1> f, Func<R1, R2> g) =>

                (T x, U y, V z) => g(f(x, y, z));

​

            Func<T0, U, R1> PreCompose<T, U, R1, T0>(Func<T, U, R1> f, Func<T0, T> g) =>

                (T0 x, U y) => f(g(x), y);

​

            Func<T0, U0, R1> PreCompose1<T, U, R1, T0, U0>(Func<T, U, R1> f, Func<T0, T> g1, Func<U0, U> g2) =>

                (T0 x, U0 y) => f(g1(x), g2(y));

​

            Func<U> Compose2<T, U>(Func<T> f, Func<T, U> g) =>

                () => g(f());

​

            Action<T> PreCompose3<T, R>(Func<T, R> g, Action<R> f) =>

                (T x) => f(g(x));

​

            void Compose4<T>(Func<T> f, Action<T> g) =>

                g(f());

​

            Func<T, R2> Compose5<T, V, R1, R2>(Func<T, (V, R1)> f, Func<V, R1, R2> g) =>

               (T x) => g(f(x).Item1, f(x).Item2);

​

            public static  void Main()       {  }

    }

}

​

​