What’s new in this edition

This section provides a list of new or updated recipes along with a short description of the change.

Chapter 1, Learning Modern Core Language Features:

• Using scope enumeration: updated with C++23 std::to_underlying and std::is_scoped_enum
• Using range-based for loops to iterate on a range: updated with the C++23 init statement
• Using the subscript operator to access elements in a collection: (new) C++23 multidimensional subscript operator

Chapter 2, Working with Numbers and Strings:

• Understanding the various numeric types: (new) explains the C++ numerical types
• Understanding the various character and string types: (new) explains the C++ character types
• Printing Unicode characters to the output console: (new) discusses working with UNICODE and printing to the console
• Creating a library of string helpers: updated with C++20 starts_with(), ends_with(), and contains()
• Formatting and printing text with std::format and std::print: updated with C++23 std::print() and std::println()
• Using std::format with user-defined types: updated with C++23 std::formattable and better examples

Chapter 3, Exploring Functions:

• Using lambdas with standard algorithms: updated with C++23 attributes on function call operators
• Writing a recursive lambda: updated with C++14 recursive generic lambdas
• Writing function templates: (new) a walkthrough of writing function templates

Chapter 4, Preprocessing and Compilation:

• Conditionally compiling your source code: updated with C++23 #warning, #elifdef, and #elifndef
• Performing compile time assertion checks with static_assert: updated with C++26 user-generated messages
• Providing metadata to the compiler with attributes: updated with C++23 attributes on lambda, [[assume]], and duplicate attributes

Chapter 5, Standard Library Containers, Algorithms, and Iterators:

• Using vector as default container: updated with C++23 range-aware member functions
• Selecting the right standard containers (new) a comparison of standard containers

Chapter 6, General-Purpose Utilities:

• Working with calendars: updated with C++20-compliant examples
• Converting times between timezones: updated with C++20-compliant examples
• Chaining together computations which may or may not produce a value: (new) discusses the C++23 std::optional monadic operations
• Using std::expected for returning a value or an error: (new) discusses the C++23 std::expected type
• Using std::mdspan for multidimensional views of sequences of objects: (new) explores the C++23 std::mdspan type
• Providing logging details with source_location: (new) explores the C++20 std::source_location type
• Using the stacktrace library to print the call stack: (new) teaches the C++23 stacktrace library

Chapter 7, Working with Files and Streams:

• Using streams on fixed-size external buffers: (new) explores the C++23 span buffers

Chapter 8, Leveraging Threading and Concurrency:

• Using thread synchronization mechanisms: updated with C++20-compliant samples
• Synchronizing output streams: (new) discusses the C++20 sync streams

Chapter 9, Robustness and Performance:

• Creating compile-time constant expressions: updated with C++23 static constexpr variables
• Optimizing code in constant-evaluated contexts: (new) explains the C++23 if consteval
• Using virtual function calls in constant expressions: (new) discusses the C++20 constexpr virtual functions

Chapter 10, Implementing Patterns and Idioms:

• Adding functionality to classes with mixins: (new) explains the mixins pattern
• Handling unrelated types generically with type erasure: (new) discusses the type erasure idiom

Chapter 11, Exploring Testing Frameworks:

• Getting started with Catch2: updated installation instructions for Catch2 version 3.4.0
• Asserting with Catch2: updated examples for Catch2 version 3.4.0

Chapter 12, C++20 Core Features:

• Exploring abbreviated function templates: (new) examines C++20 abbreviated function templates
• Exploring the standard range adaptors: (new) discusses the C++20 and C++23 range adaptors
• Converting a range to a container: (new) explains how to convert a range to a standard container using C++23 std::ranges::to()
• Using constrained algorithms: (new) explores the general-purpose algorithms that work directly with ranges
• Creating a coroutine task for asynchronous computation: updated with standard compliant examples (and alternatives with the libcoro library)
• Creating a coroutine generator type for sequences of values: updated with standard compliant examples (and alternatives with the libcoro library)
• Recursively generating values with the std::generator type: (new) explains the C++23 std::generator