using System;

public class Program {

    public static void Main() {

        var original = new IO<int>(3);

        var result = ChevronEqualIntDirect(original, x => x + 1);

        ChevronEqual(result, x => {

            Console.WriteLine(x);

            return new IO<int>(x);

        });

    }

    static IO<B> ChevronEqual<A, B>(IO<A> arg1, Func<A, IO<B>> arg2) 

        => arg1.DoChevronEqual(arg2);

​

    static IO<int> ChevronEqualIntDirect(IO<int> arg1, Func<int, int> fn) 

        => ChevronEqual(arg1, a => new IO<int>(fn(a)));

}

​

internal class IO<T> {

    private readonly T Value;

    public IO(T value) => Value = value;

    public IO<B> DoChevronEqual<B>(Func<T, IO<B>> fn) => fn(this.Value);

}

​

​