C++17 - The Complete Guide (C++17 - The Complete Guide)
C++17 - The Complete Guide
About the Book
C++17 is the next evolution in modern C++ programming, which is now supported by the latest version of gcc, clang, and Visual C++. Although it is not as big a step as C++11, it contains a large number of small and valuable language and library features, which will change the way we program in C++. As usual, not everything is self-explanatory, combining new features gives even more power, and there are hidden traps.
This book presents all the new language and library features of C++17. It covers the motivation and context of each new feature with examples and background information. The focus is on how these features impact day-to-day programming, what it means to combine them, and how to benefit from this in practice.
Testimonials:
"It's very clearly written and the examples are really helpful!" Graham Markall
"I am thoroughly enjoying the book; I had skimmed the list of changes in C++17 several times before but until I started reading your book I had no idea how substantial the changes really were. It makes me wonder what I overlooked with previous updates!" Jason Birch
"I thought I knew a bit about C++. I downloaded this book and learned something new in the *preface*. Highly recommended so far!" Tristan Brindle
Buy early, pay less, free updates
Note that this book was published step-by-step. It started with 270 pages first published in December 2018. Since then the contents grows with new chapters, examples, and caveats about the features of C++17 and I integrate all feedback I get for the pages already published.
The current version now covers all new features of C++17, both core language and library features.
See www.cppstd17.com for a detailed list of covered topics.
As written, once you bought it you will get all updates for free.
PDF versus Other Formats
I write the book in LaTeX and generate PDF from it (the way I wrote my other books). The other formats (epub, mobi, and online reading) come from the leanpub markdown interface, for which I generate the necessary input from LaTeX by script.
Thus, the PDF layout has a better quality than the other formats. For example, the syntax highlighting rules for the formats other than PDF have to get fixed as soon as possible and the index is missing yet. Leanpub and me are working on corresponding improvements.
I hope you enjoy and benefit.
Nico
#cpp17tcg
About the Author
Bundles that include this book
Table of Contents
-
-
Preface
- Versions of This Book
- Acknowledgments
-
About This Book
- What You Should Know Before Reading This Book
- Overall Structure of the Book
- How to Read This Book
- Error Terminology
- The C++17 Standard
- Example Code and Additional Information
- Feedback
-
Preface
-
I Basic Language Features
-
1. Structured Bindings
- 1.1 Structured Bindings in Detail
-
1.2 Where Structured Bindings Can Be Used
- 1.2.1 Structures and Classes
- 1.2.2 Raw Arrays
-
1.2.3
std::pair,std::tuple, andstd::array
- 1.3 Providing a Tuple-Like API for Structured Bindings
- 1.4 Afternotes
-
2.
ifandswitchwith Initialization-
2.1
ifwith Initialization -
2.2
switchwith Initialization - 2.3 Afternotes
-
2.1
-
3. Inline Variables
- 3.1 Motivation for Inline Variables
- 3.2 Using Inline Variables
-
3.3
constexprNow ImpliesinlineFor Static Members -
3.4 Inline Variables and
thread_local - 3.5 Afternotes
-
4. Aggregate Extensions
- 4.1 Motivation for Extended Aggregate Initialization
- 4.2 Using Extended Aggregate Initialization
- 4.3 Definition of Aggregates
- 4.4 Backward Incompatibilities
- 4.5 Afternotes
-
5. Mandatory Copy Elision or Passing Unmaterialized Objects
- 5.1 Motivation for Mandatory Copy Elision for Temporaries
- 5.2 Benefit of Mandatory Copy Elision for Temporaries
-
5.3 Clarified Value Categories
- 5.3.1 Value Categories
- 5.3.2 Value Categories Since C++17
- 5.4 Unmaterialized Return Value Passing
- 5.5 Afternotes
-
6. Lambda Extensions
-
6.1
constexprLambdas-
6.1.1 Using
constexprLambdas
-
6.1.1 Using
-
6.2 Passing Copies of
thisto Lambdas -
6.3 Capturing by
constReference - 6.4 Afternotes
-
6.1
-
7. New Attributes and Attribute Features
-
7.1 Attribute
[[nodiscard]] -
7.2 Attribute
[[maybe_unused]] -
7.3 Attribute
[[fallthrough]] - 7.4 General Attribute Extensions
- 7.5 Afternotes
-
7.1 Attribute
-
8. Other Language Features
- 8.1 Nested Namespaces
- 8.2 Defined Expression Evaluation Order
- 8.3 Relaxed Enum Initialization from Integral Values
-
8.4 Fixed Direct List Initialization with
auto - 8.5 Hexadecimal Floating-Point Literals
- 8.6 UTF-8 Character Literals
- 8.7 Exception Specifications as Part of the Type
-
8.8 Single-Argument
static_assert -
8.9 Preprocessor Condition
__has_include - 8.10 Afternotes
-
1. Structured Bindings
-
II Template Features
-
9. Class Template Argument Deduction
-
9.1 Use of Class Template Argument Deduction
- 9.1.1 Copying by Default
- 9.1.2 Deducing the Type of Lambdas
- 9.1.3 No Partial Class Template Argument Deduction
- 9.1.4 Class Template Argument Deduction Instead of Convenience Functions
-
9.2 Deduction Guides
- 9.2.1 Using Deduction Guides to Force Decay
- 9.2.2 Non-Template Deduction Guides
- 9.2.3 Deduction Guides versus Constructors
- 9.2.4 Explicit Deduction Guides
- 9.2.5 Deduction Guides for Aggregates
- 9.2.6 Standard Deduction Guides
- 9.3 Afternotes
-
9.1 Use of Class Template Argument Deduction
-
10. Compile-Time
if-
10.1 Motivation for Compile-Time
if -
10.2 Using Compile-Time
if-
10.2.1 Caveats for Compile-Time
if -
10.2.2 Other Compile-Time
ifExamples
-
10.2.1 Caveats for Compile-Time
-
10.3 Compile-Time
ifwith Initialization -
10.4 Using Compile-Time
ifOutside Templates - 10.5 Afternotes
-
10.1 Motivation for Compile-Time
-
11. Fold Expressions
- 11.1 Motivation for Fold Expressions
-
11.2 Using Fold Expressions
- 11.2.1 Dealing with Empty Parameter Packs
- 11.2.2 Supported Operators
- 11.2.3 Using Fold Expressions for Types
- 11.3 Afternotes
-
12. Dealing with String Literals as Template Parameters
- 12.1 Using Strings in Templates
- 12.2 Afternotes
-
13. Placeholder Types like
autoas Template Parameters-
13.1 Using
autofor Template Parameters- 13.1.1 Parameterizing Templates for Characters and Strings
- 13.1.2 Defining Metaprogramming Constants
-
13.2 Using
autoas Variable Template Parameter -
13.3 Using
decltype(auto)as Template Parameter - 13.4 Afternotes
-
13.1 Using
-
14. Extended Using Declarations
- 14.1 Using Variadic Using Declarations
- 14.2 Variadic Using Declarations for Inheriting Constructors
- 14.3 Afternotes
-
9. Class Template Argument Deduction
-
III New Library Components
-
15.
std::optional<>-
15.1 Using
std::optional<>- 15.1.1 Optional Return Values
- 15.1.2 Optional Arguments and Data Members
-
15.2
std::optional<>Types and Operations-
15.2.1
std::optional<>Types -
15.2.2
std::optional<>Operations
-
15.2.1
-
15.3 Special Cases
- 15.3.1 Optional of Boolean or Raw Pointer Values
- 15.3.2 Optional of Optional
- 15.4 Afternotes
-
15.1 Using
-
16.
std::variant<>-
16.1 Motivation for
std::variant<> -
16.2 Using
std::variant<> -
16.3
std::variant<>Types and Operations-
16.3.1
std::variant<>Types -
16.3.2
std::variant<>Operations - 16.3.3 Visitors
- 16.3.4 Valueless by Exception
-
16.3.1
-
16.4 Polymorphism and Heterogeneous Collections with
std::variant-
16.4.1 Geometric Objects with
std::variant -
16.4.2 Other Heterogeneous Collections with
std::variant -
16.4.3 Comparing
variantPolymorphism
-
16.4.1 Geometric Objects with
-
16.5 Special Cases with
std::variant<>-
16.5.1 Having Both
boolandstd::stringAlternatives
-
16.5.1 Having Both
- 16.6 Afternotes
-
16.1 Motivation for
-
17.
std::any-
17.1 Using
std::any -
17.2
std::anyTypes and Operations- 17.2.1 Any Types
- 17.2.2 Any Operations
- 17.3 Afternotes
-
17.1 Using
-
18.
std::byte-
18.1 Using
std::byte -
18.2
std::byteTypes and Operations-
18.2.1
std::byteTypes -
18.2.2
std::byteOperations
-
18.2.1
- 18.3 Afternotes
-
18.1 Using
-
19. String Views
-
19.1 Differences Compared to
std::string - 19.2 Using String Views
-
19.3 Using String Views as Parameters
- 19.3.1 String View Considered Harmful
-
19.4 String View Types and Operations
- 19.4.1 Concrete String View Types
- 19.4.2 String View Operations
- 19.4.3 String View Support by Other Types
-
19.5 Using String Views in APIs
- 19.5.1 Using String Views instead of Strings
- 19.6 Afternotes
-
19.1 Differences Compared to
-
20. The Filesystem Library
-
20.1 Basic Examples
- 20.1.1 Print Attributes of a Passed Filesystem Path
- 20.1.2 Switch Over Filesystem Types
- 20.1.3 Create Different Types of Files {#createfiles.cpp}
- 20.1.4 Dealing with Filesystems Using Parallel Algorithms
-
20.2 Principles and Terminology
- 20.2.1 General Portability Disclaimer
- 20.2.2 Namespace
- 20.2.3 Paths
- 20.2.4 Normalization
- 20.2.5 Member Function versus Free-Standing Functions
- 20.2.6 Error Handling
- 20.2.7 File Types
-
20.3 Path Operations
- 20.3.1 Path Creation
- 20.3.2 Path Inspection
- 20.3.3 Path I/O and Conversions
- 20.3.4 Conversions Between Native and Generic Format
- 20.3.5 Path Modifications
- 20.3.6 Path Comparisons
- 20.3.7 Other Path Operations
-
20.4 Filesystem Operations
- 20.4.1 File Attributes
- 20.4.2 File Status
- 20.4.3 Permissions
- 20.4.4 Filesystem Modifications
- 20.4.5 Symbolic Links and Filesystem-Dependent Path Conversions
- 20.4.6 Other Filesystem Operations
-
20.5 Iterating Over Directories
- 20.5.1 Directory Entries
- 20.6 Afternotes
-
20.1 Basic Examples
-
15.
-
IV Library Extensions and Modifications
-
21. Extensions of Type Traits
-
21.1 Type Traits Suffix
_v - 21.2 New Type Traits
- 21.3 Afternotes
-
21.1 Type Traits Suffix
-
22. Parallel STL Algorithms
-
22.1 Using Parallel Algorithms
-
22.1.1 Using a Parallel
for_each() -
22.1.2 Using a Parallel
sort()
-
22.1.1 Using a Parallel
- 22.2 Execution Policies
- 22.3 Exception Handling
- 22.4 Benefit of Not Using Parallel Algorithms
- 22.5 Overview of Parallel Algorithms
-
22.6 Motivation for New Algorithms for Parallel Processing
-
22.6.1
reduce()
-
22.6.1
- 22.7 Afternotes
-
22.1 Using Parallel Algorithms
-
23. New STL Algorithms in Detail
-
23.1
std::for_each_n() -
23.2 New Numeric STL Algorithms
-
23.2.1
std::reduce() -
23.2.2
std::transform_reduce() -
23.2.3
std::inclusive_scan()andstd::exclusive_scan() -
23.2.4
std::transform_inclusive_scan()andstd::transform_exclusive_scan()
-
23.2.1
- 23.3 Afternotes
-
23.1
-
24. Substring and Subsequence Searchers
-
24.1 Using Substring Searchers
-
24.1.1 Using Searchers with
search() - 24.1.2 Using Searchers Directly
-
24.1.1 Using Searchers with
- 24.2 Using General Subsequence Searchers
- 24.3 Using Searcher Predicates
- 24.4 Afternotes
-
24.1 Using Substring Searchers
-
25. Other Utility Functions and Algorithms
-
25.1
size(),empty(), anddata()-
25.1.1 Generic
size()Function -
25.1.2 Generic
empty()Function -
25.1.3 Generic
data()Function
-
25.1.1 Generic
-
25.2
as_const()- 25.2.1 Capturing by Const Reference
-
25.3
clamp() -
25.4
sample() - 25.5 Afternotes
-
25.1
-
26. Container and String Extensions
-
26.1 Node Handles
- 26.1.1 Modifying a Key
- 26.1.2 Moving Nodes Between Containers
- 26.1.3 Merging Containers
-
26.2 Emplace Improvements
- 26.2.1 Return Type of Emplace Functions
-
26.2.2
try_emplace()andinsert_or_assign()for Maps
- 26.3 Container Support for Incomplete Types
- 26.4 String Improvements
- 26.5 Afternotes
-
26.1 Node Handles
-
27. Multi-Threading and Concurrency
-
27.1 Supplementary Mutexes and Locks
-
27.1.1
std::scoped_lock -
27.1.2
std::shared_mutex
-
27.1.1
-
27.2
is_always_lock_freefor Atomics - 27.3 Cache Line Sizes
- 27.4 Afternotes
-
27.1 Supplementary Mutexes and Locks
-
28. Other Small Library Features and Modifications
-
28.1
std::uncaught_exceptions() -
28.2 Shared Pointer Improvements
- 28.2.1 Special handling for Shared Pointers to Raw C Arrays
-
28.2.2
reinterpret_pointer_castfor Shared Pointers -
28.2.3
weak_typefor Shared Pointers -
28.2.4
weak_from_thisfor Shared Pointers
-
28.3 Numeric Extensions
- 28.3.1 Greatest Common Divisor and Least Common Multiple
-
28.3.2 Three-Argument Overloads of
std::hypot() - 28.3.3 Mathematical Special Functions
-
28.4
chronoExtensions -
28.5
constexprExtensions and Fixes -
28.6
noexceptExtensions and Fixes - 28.7 Afternotes
-
28.1
-
21. Extensions of Type Traits
-
V Expert Utilities
-
29. Polymorphic Memory Resources (PMR)
-
29.1 Using Standard Memory Resources
- 29.1.1 Motivating Example
- 29.1.2 Standard Memory Resources
- 29.1.3 Standard Memory Resources in Detail
-
29.2 Defining Custom Memory Resources
- 29.2.1 Equality of Memory Resources
-
29.3 Providing Memory Resource Support for Custom Types
- 29.3.1 Definition of a PMR Type
- 29.3.2 Using a PMR Type
- 29.3.3 Dealing with the Different Types
- 29.4 Afternotes
-
29.1 Using Standard Memory Resources
-
30.
newanddeletewith Over-Aligned Data-
30.1 Using
newwith Alignments- 30.1.1 Distinct Dynamic/Heap Memory Arenas
-
30.1.2 Passing the Alignment with the
newExpression
-
30.2 Implementing
operator new()for Aligned Memory- 30.2.1 Implementing Aligned Allocation Before C++17
-
30.2.2 Implementing Type-Specific
operator new()
-
30.3 Implementing Global
operator new()- 30.3.1 Backward Incompatibilities
-
30.4 Tracking All
::newCalls - 30.5 Afternotes
-
30.1 Using
-
31.
std::to_chars()andstd::from_chars()- 31.1 Motivation for Low-Level Conversions between Character Sequences and Numeric Values
-
31.2 Example Usage
-
31.2.1
from_chars() -
31.2.2
to_chars()
-
31.2.1
- 31.3 Floating-Point Round-Trip Support
- 31.4 Afternotes
-
32.
std::launder()-
32.1 Motivation for
std::launder() -
32.2 How
launder()Solves the Problem -
32.3 Why/When
launder()Does Not Work - 32.4 Afternotes
-
32.1 Motivation for
-
33. Improvements for Implementing Generic Code
-
33.1
std::invoke<>() -
33.2
std::bool_constant<> -
33.3
std::void_t<> - 33.4 Afternotes
-
33.1
-
29. Polymorphic Memory Resources (PMR)
-
VI Final General Hints
-
34. Common C++17 Settings
-
34.1 Value of
__cplusplus - 34.2 Compatibility to C11
- 34.3 Dealing with Signal Handlers
- 34.4 Forward Progress Guarantees
- 34.5 Afternotes
-
34.1 Value of
-
35. Deprecated and Removed Features
-
35.1 Deprecated and Removed Core Language Features
- 35.1.1 Throw Specifications
-
35.1.2 Keyword
register -
35.1.3 Disable
++forbool - 35.1.4 Trigraphs
-
35.1.5 Definition/Redeclaration of
staticconstexprMembers
-
35.2 Deprecated and Removed Library Features
-
35.2.1
auto_ptr -
35.2.2 Algorithm
random_shuffle() -
35.2.3
unary_functionandbinary_function -
35.2.4
ptr_fun(),mem_fun(), and Binders -
35.2.5 Allocator Support for
std::function<> - 35.2.6 Deprecated IOStream Aliases
- 35.2.7 Deprecated Library Features
-
35.2.1
- 35.3 Afternotes
-
35.1 Deprecated and Removed Core Language Features
-
Glossary
-
B
- bitmask type
-
F
- full specialization
-
I
- incomplete type
-
P
- partial specialization
-
S
- small/short string optimization (SSO)
-
V
- variable template
- variadic template
-
B
-
34. Common C++17 Settings
- Notes
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