Curry.cs

namespace Curry
{
    using System;

    internal static class Program
    {
        // Curry methods
        public static TResult Curry<T, TResult>(this Func<T, TResult> f, T arg)
        {
            // Curry'2 is just invoke
            return f.Invoke(arg);
        }

        public static Func<T2, TResult> Curry<T1, T2, TResult>(this Func<T1, T2, TResult> f, T1 arg1)
        {
            return arg2 => f.Invoke(arg1, arg2);
        }

        public static Func<T2, T3, TResult> Curry<T1, T2, T3, TResult>(this Func<T1, T2, T3, TResult> f, T1 arg1)
        {
            return (arg2, arg3) => f.Invoke(arg1, arg2, arg3);
        }

        // Test Methods
        public static int Square(int x)
        {
            return x * x;
        }

        public static int Add(int x, int y)
        {
            return x + y;
        }

        public static int Sum(int x, int y, int z)
        {
            return x + y + z;
        }

        public static double Pown(double @base, int exponent)
        {
            if (exponent < 0)
            {
                throw new ArgumentException("Exponent cannot be negative", "exponent");
            }

            double result = 1;
            for (int i = 0; i < exponent; i++)
            {
                result *= @base;
            }

            return result;
        }

        // Program entry point
        internal static void Main(string[] args)
        {
            Console.WriteLine("Square 2 = {0}", Curry(Square, 2));

            // Call Curry with named function
            var add1 = Curry<int, int, int>(Add, 1);
            Console.WriteLine("add1 3 = {0}", add1.Invoke(3));

            // Call curry with Func object
            Func<int, int, int> add = Add;
            var add2 = add.Curry(2);
            Console.WriteLine("add2 4 = {0}", add2.Invoke(4));

            // Call curry with lambda
            Func<int, int, int> addLambda = (x, y) => x + y;
            var add3 = addLambda.Curry(3);
            Console.WriteLine("add3 5 = {0}", add3.Invoke(5));

            // Call curry with differing parameter types
            Func<double, int, double> pown = Pown;
            var threeToThe = pown.Curry(3.0);
            Console.WriteLine("threeToThe 2 = {0}", threeToThe(2));

            // Curry'4
            Func<int, int, int, int> sum = Sum;
            var add4 = sum.Curry(1).Curry(3);

            Console.WriteLine("add4 6 = {0}", add4(6));
            Console.WriteLine("add5 7 = {0}", sum.Curry(2).Curry(3).Curry(7));

            Console.WriteLine();
            Console.Write("Press any key to continue . . . ");
            Console.ReadKey(true);
        }
    }
}