How to access the sample code on GitHub

What you should know

Functional programming patterns

What is functional programming

Core principles of functional programming

Monads, currying and other terms

The functional parts of C#

Function categories

Write pure functions for better code

Example of an impure function

Refactor impure function to pure

Don't mutate input arguments

Use an immutable argument

Reduce code side effects

What about impure class properties

Refactor side effect example

Work with files

Filter with LINQ Where

Calculate the total in a pure function

Functional function concepts

Use FuncT for first class functions

Higher-order LINQ

Higher-order filter example

Higher-order transform example

Return function from function call

Simple immutable example

More principles

Principles of immutable types

Read-only properties

Instance method in immutable type

Use factory method to create instance

Use helper methods to create new instance

Why expressions are better for functional programs

Some examples of C# expressions

Rewrite IF statement with expression

Rewrite SWITCH statement with expression

Rewrite FOREACH with expression

IsPrime function as an expression

Learn the composition patterns

Compose functions

Pipelining with extension methods

Pipelining with generic methods

Pipelining with IEnumerable

Understand Map and other concepts

Map with LINQ SELECT

Map to a different type

Join with SelectMany

Filter with LINQ WHERE

Flatten with SelectMany

Fold with SUM and AGGREGATE

Randomness in functional programming

A functional Random class

Extension methods for various types

Specify a smaller range of random numbers

Randomize the order of a list

Create a random list

Replace VOID with the UNIT class

Replace NULL with OPTION

Explore the Either type for error handling

Next steps