C++20 for Programmers: An Objects-Natural Approach

The professional programmer's Deitel® guide to C++20 Written for programmers with a background in another high-level language, in this book, you'll learn Modern C++ development hands on using C++20 and its "Big Four" features--Ranges, Concepts, Modules and Coroutines. (For more details, see the Preface, and the table of contents diagram inside the front cover.) In the context of 200+, hands-on, real-world code examples, you'll quickly master Modern C++ coding idioms using popular compilers--Visual C++®, GNU® g++, Apple® Xcode® and LLVM®/Clang. After the C++ fundamentals quick start, you'll move on to C++ standard library containers array and vector; functional-style programming with C++20 Ranges and Views; strings, files and regular expressions; object-oriented programming with classes, inheritance, runtime polymorphism and static polymorphism; operator overloading, copy/move semantics, RAII and smart pointers; exceptions and a look forward to C++23 Contracts; standard library containers, iterators and algorithms; templates, C++20 Concepts and metaprogramming; C++20 Modules and large-scale development; and concurrency, parallelism, the C++17 and C++20 parallel standard library algorithms and C++20 Coroutines. Features Rich coverage of C++20's "Big Four": Ranges, Concepts, Modules and Coroutines Objects-Natural Approach: Use standard libraries and open-source libraries to build significant applications with minimal code Hundreds of real-world, live-code examples Modern C++: C++20, 17, 14, 11 and a look to C++23 Compilers: Visual C++®, GNU® g++, Apple Xcode® Clang, LLVM®/Clang Docker: GNU® GCC, LLVM®/Clang Fundamentals: Control statements, functions, strings, references, pointers, files, exceptions Object-oriented programming: Classes, objects, inheritance, runtime and static polymorphism, operator overloading, copy/move semantics, RAII, smart pointers Functional-style programming: C++20 Ranges and Views, lambda expressions Generic programming: Templates, C++20 Concepts and metaprogramming C++20 Modules: Large-Scale Development Concurrent programming: Concurrency, multithreading, parallel algorithms, C++20 Coroutines, coroutines support libraries, C++23 executors Future: A look forward to Contracts, range-based parallel algorithms, standard library coroutine support and more "C++20 for Programmers builds up an intuition for modern C++ that every programmer should have in the current software engineering ecosystem. The unique and brilliant ordering in which the Deitels present the material jibes much more naturally with the demands of modern, production-grade programming environments. I strongly recommend this book for anyone who needs to get up to speed on C++, particularly in professional programming environments where the idioms and patterns of modern C++ can be indecipherable without the carefully crafted guidance that this book provides." --Dr. Daisy Hollman, ISO C++ Standards Committee Member "This is a fine book that covers a surprising amount of the very large language that is C++20. An in-depth treatment of C++ for a reader familiar with how things work in other programming languages." --Arthur O'Dwyer, C++ trainer, Chair of CppCon's Back to Basics track, author of several accepted C++17/20/23 proposals and the book Mastering the C++17 STL "Forget about callback functions, bare pointers and proprietary multithreading libraries--C++20 is about standard concurrency features, generic lambda expressions, metaprogramming, tighter type-safety and the long-awaited concepts, which are all demonstrated in this book. Functional programming is explained clearly with plenty of illustrative code listings. The excellent chapter, 'Parallel Algorithms and Concurrency: A High-Level View,' is a highlight of this book." --Danny Kalev, Ph.D. and Certified System Analyst and Software Engineer, Former ISO C++ Standards Committee Member Register your book for convenient access to downloads, updates, and/or corrections as they become available. See inside book for details. Note: eBooks are 4-color and print books are black and white.

Table of Contents:
Preface xxi Before You Begin xliii Chapter 1: Intro and Test-Driving Popular, Free C++ Compilers 1 1.1 Introduction 2 1.2 Test-Driving a C++20 Application 4 1.3 Moore's Law, Multi-Core Processors and Concurrent Programming 16 1.4 A Brief Refresher on Object Orientation 17 1.5 Wrap-Up 20 Chapter 2: Intro to C++20 Programming 21 2.1 Introduction 22 2.2 First Program in C++: Displaying a Line of Text 22 2.3 Modifying Our First C++ Program 25 2.4 Another C++ Program: Adding Integers 26 2.5 Arithmetic 30 2.6 Decision Making: Equality and Relational Operators 31 2.7 Objects Natural: Creating and Using Objects of Standard-Library Class string 35 2.8 Wrap-Up 38 Chapter 3: Control Statements: Part 1 39 3.1 Introduction 40 3.2 Control Structures 40 3.3 if Single-Selection Statement 43 3.4 if…else Double-Selection Statement 44 3.5 while Iteration Statement 47 3.6 Counter-Controlled Iteration 48 3.7 Sentinel-Controlled Iteration 50 3.8 Nested Control Statements 54 3.9 Compound Assignment Operators 57 3.10 Increment and Decrement Operators 58 3.11 Fundamental Types Are Not Portable 60 3.12 Objects-Natural Case Study: Arbitrary-Sized Integers 61 3.13 C++20: Text Formatting with Function format 65 3.14 Wrap-Up 67 Chapter 4: Control Statements: Part 2 69 4.1 Introduction 70 4.2 Essentials of Counter-Controlled Iteration 70 4.3 for Iteration Statement 71 4.4 Examples Using the for Statement 74 4.5 Application: Summing Even Integers 74 4.6 Application: Compound-Interest Calculations 75 4.7 do…while Iteration Statement 78 4.8 switch Multiple-Selection Statement 80 4.9 C++17 Selection Statements with Initializers 85 4.10 break and continue Statements 86 4.11 Logical Operators 88 4.12 Confusing the Equality (==) and Assignment (=) Operators 92 4.13 Objects-Natural Case Study: Using the miniz-cpp Library to Write and Read ZIP files 94 4.14 C++20 Text Formatting with Field Widths and Precisions 98 4.15 Wrap-Up 100 Chapter 5: Functions and an Intro to Function Templates 101 5.1 Introduction 102 5.2 C++ Program Components 103 5.3 Math Library Functions 103 5.4 Function Definitions and Function Prototypes 105 5.5 Order of Evaluation of a Function's Arguments 108 5.6 Function-Prototype and Argument-Coercion Notes 108 5.7 C++ Standard Library Headers 111 5.8 Case Study: Random-Number Generation 113 5.9 Case Study: Game of Chance; Introducing Scoped enums 119 5.10 Scope Rules 124 5.11 Inline Functions 128 5.12 References and Reference Parameters 129 5.13 Default Arguments 132 5.14 Unary Scope Resolution Operator 133 5.15 Function Overloading 134 5.16 Function Templates 137 5.17 Recursion 139 5.18 Example Using Recursion: Fibonacci Series 142 5.19 Recursion vs. Iteration 145 5.20 Lnfylun Lhqtomh Wjtz Qarcv: Qjwazkrplm xzz Xndmwwqhlz 147 5.21 Wrap-Up 150 Chapter 6:  arrays, vectors, Ranges and Functional-Style Programming 153 6.1 Introduction 154 6.2 arrays 155 6.3 Declaring arrays 155 6.4 Initializing array Elements in a Loop 155 6.5 Initializing an array with an Initializer List 158 6.6 C++11 Range-Based for and C++20 Range-Based for with Initializer 159 6.7 Calculating array Element Values and an Intro to constexpr 161 6.8 Totaling array Elements 163 6.9 Using a Primitive Bar Chart to Display array Data Graphically 164 6.10 Using array Elements as Counters 165 6.11 Using arrays to Summarize Survey Results 166 6.12 Sorting and Searching arrays 168 6.13 Multidimensional arrays 170 6.14 Intro to Functional-Style Programming 174 6.15 Objects-Natural Case Study: C++ Standard Library Class Template vector 180 6.16 Wrap-Up 187 Chapter 7: (Downplaying) Pointers in Modern C++ 189 7.1 Introduction 190 7.2 Pointer Variable Declarations and Initialization 192 7.3 Pointer Operators 192 7.4 Pass-by-Reference with Pointers 195 7.5 Built-In Arrays 199 7.6 Using C++20 to_array to Convert a Built-In Array to a std::array 201 7.7 Using const with Pointers and the Data Pointed To 202 7.8 sizeof Operator 205 7.9 Pointer Expressions and Pointer Arithmetic 208 7.10 Objects-Natural Case Study: C++20 spans--Views of Contiguous Container Elements 210 7.11 A Brief Intro to Pointer-Based Strings 216 7.12 Looking Ahead to Other Pointer Topics 220 7.13 Wrap-Up 220 Chapter 8: strings, string_views, Text Files, CSV Files and Regex 221 8.1 Introduction 222 8.2 string Assignment and Concatenation 223 8.3 Comparing strings 225 8.4 Substrings 226 8.5 Swapping strings 227 8.6 string Characteristics 227 8.7 Finding Substrings and Characters in a string 230 8.8 Replacing and Erasing Characters in a string 232 8.9 Inserting Characters into a string 234 8.10 C++11 Numeric Conversions 235 8.11 C++17 string_view 236 8.12 Files and Streams 239 8.13 Creating a Sequential File 240 8.14 Reading Data from a Sequential File 243 8.15 C++14 Reading and Writing Quoted Text 245 8.16 Updating Sequential Files 246 8.17 String Stream Processing 247 8.18 Raw String Literals 249 8.19 Objects-Natural Case Study: Reading and Analyzing a CSV File Containing Titanic Disaster Data 250 8.20 Objects-Natural Case Study: Intro to Regular Expressions 259 8.21 Wrap-Up 267 Chapter 9: Custom Classes 269 9.1 Introduction 270 9.2 Test-Driving an Account Object 271 9.3 Account Class with a Data Member and Set and Get Member Functions 272 9.4 Account Class: Custom Constructors 275 9.5 Software Engineering with Set and Get Member Functions 279 9.6 Account Class with a Balance 280 9.7 Time Class Case Study: Separating Interface from Implementation 283 9.8 Compilation and Linking Process 290 9.9 Class Scope and Accessing Class Members 291 9.10 Access Functions and Utility Functions 292 9.11 Time Class Case Study: Constructors with Default Arguments 292 9.12 Destructors 298 9.13 When Constructors and Destructors Are Called 298 9.14 Time Class Case Study: A Subtle Trap--Returning a Reference or a Pointer to a private Data Member 302 9.15 Default Assignment Operator 304 9.16 const Objects and const Member Functions 306 9.17 Composition: Objects as Members of Classes 308 9.18 friend Functions and friend Classes 313 9.19 The this Pointer 314 9.20 static Class Members: Classwide Data and Member Functions 320 9.21 Aggregates in C++20 324 9.22 Objects-Natural Case Study: Serialization with JSON 326 9.23 Wrap-Up 333 Chapter 10: OOP: Inheritance and Runtime Polymorphism 335 10.1 Introduction 336 10.2 Base Classes and Derived Classes 339 10.3 Relationship Between Base and Derived Classes 341 10.4 Constructors and Destructors in Derived Classes 349 10.5 Intro to Runtime Polymorphism: Polymorphic Video Game 350 10.6 Relationships Among Objects in an Inheritance Hierarchy 351 10.7 Virtual Functions and Virtual Destructors 357 10.8 Abstract Classes and Pure virtual Functions 362 10.9 Case Study: Payroll System Using Runtime Polymorphism 363 10.10 Runtime Polymorphism, Virtual Functions and Dynamic Binding "Under the Hood" 373 10.11 Non-Virtual Interface (NVI) Idiom 376 10.12 Program to an Interface, Not an Implementation 383 10.13 Runtime Polymorphism with std::variant and std::visit 391 10.14 Multiple Inheritance 397 10.15 protected Class Members: A Deeper Look 405 10.16 public, protected and private Inheritance 406 10.17 More Runtime Polymorphism Techniques; Compile-Time Polymorphism 408 10.18 Wrap-Up 412 Chapter 11: Operator Overloading, Copy/Move Semantics and Smart Pointers 415 11.1 Introduction 416 11.2 Using the Overloaded Operators of Standard Library Class string 418 11.3 Operator Overloading Fundamentals 423 11.4 (Downplaying) Dynamic Memory Management with new and delete 425 11.5 Modern C++ Dynamic Memory Management: RAII and Smart Pointers 427 11.6 MyArray Case Study: Crafting a Valuable Class with Operator Overloading 430 11.7 C++20 Three-Way Comparison Operator (<=>) 459 11.8 Converting Between Types 462 11.9 explicit Constructors and Conversion Operators 463 11.10 Overloading the Function Call Operator () 466 11.11 Wrap-Up 466 Chapter 12: Exceptions and a Look Forward to Contracts 467 12.1 Introduction 468 12.2 Exception-Handling Flow of Control 471 12.3 Exception Safety Guarantees and noexcept 476 12.4 Rethrowing an Exception 477 12.5 Stack Unwinding and Uncaught Exceptions 479 12.6 When to Use Exception Handling 481 12.7 Constructors, Destructors and Exception Handling 483 12.8 Processing new Failures 487 12.9 Standard Library Exception Hierarchy 490 12.10 C++'s Alternative to the finally Block: Resource Acquisition Is Initialization (RAII) 493 12.11 Some Libraries Support Both Exceptions and Error Codes 493 12.12 Logging 494 12.13 Looking Ahead to Contracts 495 12.14 Wrap-Up 503 Chapter 13: Standard Library Containers and Iterators 505 13.1 Introduction 506 13.2 Introduction to Containers 508 13.3 Working with Iterators 513 13.4 A Brief Introduction to Algorithms 518 13.5 Sequence Containers 518 13.6 vector Sequence Container 519 13.7 list Sequence Container 526 13.8 deque Sequence Container 531 13.9 Associative Containers 533 13.10 Container Adaptors 543 13.11 bitset Near Container 547 13.12 Optional: A Brief Intro to Big O 549 13.13 Optional: A Brief Intro to Hash Tables 552 13.14 Wrap-Up 553 Chapter 14: Standard Library Algorithms and C++20 Ranges & Views 555 14.1 Introduction 556 14.2 Algorithm Requirements: C++20 Concepts 558 14.3 Lambdas and Algorithms 560 14.4 Algorithms 563 14.5 Function Objects (Functors) 603 14.6 Projections 608 14.7 C++20 Views and Functional-Style Programming 611 14.8 Intro to Parallel Algorithms 617 14.9 Standard Library Algorithm Summary 619 14.10 A Look Ahead to C++23 Ranges 622 14.11 Wrap-Up 623 Chapter 15: Templates, C++20 Concepts and Metaprogramming 625 15.1 Introduction 626 15.2 Custom Class Templates and Compile-Time Polymorphism 629 15.3 C++20 Function Template Enhancements 634 15.4 C++20 Concepts: A First Look 636 15.5 Type Traits 644 15.6 C++20 Concepts: A Deeper Look 648 15.7 Testing C++20 Concepts with static_assert 659 15.8 Creating a Custom Algorithm 661 15.9 Creating a Custom Container and Iterators 663 15.10 Default Arguments for Template Type Parameters 678 15.11 Variable Templates 678 15.12 Variadic Templates and Fold Expressions 679 15.13 Template Metaprogramming 693 15.14 Wrap-Up 705 Chapter 16: C++20 Modules: Large-Scale Development 707 16.1 Introduction 708 16.2 Compilation and Linking Before C++20 710 16.3 Advantages and Goals of Modules 711 16.4 Example: Transitioning to Modules--Header Units 712 16.5 Modules Can Reduce Translation Unit Sizes and Compilation Times 715 16.6 Example: Creating and Using a Module 716 16.7 Global Module Fragment 724 16.8 Separating Interface from Implementation 725 16.9 Partitions 732 16.10 Additional Modules Examples 740 16.11 Migrating Code to Modules 746 16.12 Future of Modules and Modules Tooling 746 16.13 Wrap-Up 748 Chapter 17: Parallel Algorithms and Concurrency: A High-Level View 755 17.1 Introduction 756 17.2 Standard Library Parallel Algorithms (C++17) 759 17.3 Multithreaded Programming 767 17.4 Launching Tasks with std::jthread 771 17.5 Producer–Consumer Relationship: A First Attempt 776 17.6 Producer–Consumer: Synchronizing Access to Shared Mutable Data 783 17.7 Producer–Consumer: Minimizing Waits with a Circular Buffer 795 17.8 Readers and Writers 804 17.9 Cooperatively Canceling jthreads 805 17.10 Launching Tasks with std::async 808 17.11 Thread-Safe, One-Time Initialization 815 17.12 A Brief Introduction to Atomics 816 17.13 Coordinating Threads with C++20 Latches and Barriers 820 17.14 C++20 Semaphores 826 17.15 C++23: A Look to the Future of C++ Concurrency 830 17.16 Wrap-Up 831 Chapter 18: C++20 Coroutines 833 18.1 Introduction 834 18.2 Coroutine Support Libraries 835 18.3 Installing the concurrencpp and generator Libraries 837 18.4 Creating a Generator Coroutine with co_yield and the generator Library 837 18.5 Launching Tasks with concurrencpp 841 18.6 Creating a Coroutine with co_await and co_return 845 18.7 Low-Level Coroutines Concepts 853 18.8 C++23 Coroutines Enhancements 855 18.9 Wrap-Up 856 Appendix A: Operator Precedence and Grouping 857 Appendix B: Character Set 859 Index 861 Online Chapters and Appendices Chapter 19: Stream I/O and C++20 Text Formatting Chapter 20: Other Topics and a Look Toward the Future of C++ Appendix C: Number Systems Appendix D: Preprocessor Appendix E: Bit Manipulation