AnonymousFunctionsVsLocalFunctions.cs

using System;

namespace AnonymousFunctionsVsLocalFunctions
{
    public class Program
    {
        public static void Main(string[] args)
        {
            var functions = new Functions();

            Console.WriteLine(functions.PerformAnonymousFunction());
            Console.WriteLine(functions.PerformAnonymousFunctionWithParam());
            Console.WriteLine(functions.PerformAnonymousFunctionWithParamAsCallback());
            Console.WriteLine(functions.PerformAnonymousFunctionWithLocal());
            Console.WriteLine(functions.PerformAnonymousFunctionWithMember());
            Console.WriteLine(functions.PerformAnonymousFunctionWithLocalSideEffect());
            Console.WriteLine(functions.PerformAnonymousFunctionWithLocalSideEffectAsCallback());
            Console.WriteLine(functions.PerformAnonymousFunctionWithMemberSideEffect());

            Console.WriteLine(functions.PerformLocalFunction());
            Console.WriteLine(functions.PerformLocalFunctionWithParam());
            Console.WriteLine(functions.PerformLocalFunctionWithParamAsCallback());
            Console.WriteLine(functions.PerformLocalFunctionWithLocal());
            Console.WriteLine(functions.PerformLocalFunctionWithMember());
            Console.WriteLine(functions.PerformLocalFunctionWithLocalSideEffect());
            Console.WriteLine(functions.PerformLocalFunctionWithLocalSideEffectAsCallback());
            Console.WriteLine(functions.PerformLocalFunctionWithMemberSideEffect());
        }
    }

    public class Functions
    {
        private int _value = 0;

        public int PerformAnonymousFunction()
        {
            Func<int> func = () => 1;
            return func();
        }

        public int PerformAnonymousFunctionWithParam()
        {
            Func<int, int> func = x => x + 1;
            return func(1);
        }

        public int PerformAnonymousFunctionWithParamAsCallback()
        {
            Func<int, int> func = x => x + 1;
            return Invoke(func, 1);
        }

        public int PerformAnonymousFunctionWithLocal()
        {
            int x = 1;
            Func<int> func = () => x + 1;
            return func();
        }

        public int PerformAnonymousFunctionWithMember()
        {
            Func<int> func = () => _value + 1;
            return func();
        }

        public int PerformAnonymousFunctionWithLocalSideEffect()
        {
            int x = 1;
            Func<int> func = () => ++x;
            return func();
        }

        public int PerformAnonymousFunctionWithLocalSideEffectAsCallback()
        {
            int x = 1;
            Func<int> func = () => ++x;
            return Invoke(func);
        }

        public int PerformAnonymousFunctionWithMemberSideEffect()
        {
            Func<int> func = () => ++_value;
            return func();
        }

        public int PerformLocalFunction()
        {
            int func() => 1;
            return func();
        }

        public int PerformLocalFunctionWithParam()
        {
            int func(int x) => x + 1;
            return func(1);
        }

        public int PerformLocalFunctionWithParamAsCallback()
        {
            int func(int x) => x + 1;
            return Invoke(func, 1);
        }

        public int PerformLocalFunctionWithLocal()
        {
            int x = 1;
            int func() => x + 1;
            return func();
        }

        public int PerformLocalFunctionWithMember()
        {
            int func() => _value + 1;
            return func();
        }

        public int PerformLocalFunctionWithLocalSideEffect()
        {
            int x = 1;
            int func() => ++x;
            return func();
        }

        public int PerformLocalFunctionWithLocalSideEffectAsCallback()
        {
            int x = 1;
            int func() => ++x;
            return Invoke(func);
        }

        public int PerformLocalFunctionWithMemberSideEffect()
        {
            int func() => ++_value;
            return func();
        }

        private int Invoke(Func<int> func) => func();

        private int Invoke(Func<int, int> func, int arg) => func(arg);
    }
}