Professional C# 7 and .NET Core 2.0, 7th Edition

13Functional Programming with C#

WHAT’S IN THIS CHAPTER?

• Functional programming overview
• Expression-bodied members
• Extension methods
• The using static declaration
• Local functions
• Tuples
• Pattern matching

WROX.COM CODE DOWNLOADS FOR THIS CHAPTER

You can find the Wrox.com code downloads for this chapter at www.wrox.com. The source code is also available at https://github.com/ProfessionalCSharp/ProfessionalCSharp7 in the directory FunctionalProgramming.

The code for this chapter is divided into the following major examples:

• ExpressionBodiedMembers
• LocalFunctions
• Tuples
• PatternMatching

WHAT IS FUNCTIONAL PROGRAMMING?

C# never has been a pure object-oriented programming language. From the beginning, C# has been a component-oriented programming language. What does component-oriented mean? C# offers inheritance and polymorphism that’s also used by object-oriented programming languages; in addition, it offers native support for properties, events, and annotations via attributes. Later versions with LINQ and expressions have also included declarative programming. Using declarative LINQ expressions, the compiler saves an expression tree that is used later by a provider to dynamically generate SQL statements.

NOTE

Object-oriented features of C# are discussed in Chapter 4, “Object-Oriented Programming with C#,” events are covered in Chapter 8, “Delegates, Lambdas, and Events,” and LINQ is covered in Chapter 12, “Language Integrated Query.”

C# is not purely bound to a single ...