C++20 - The Complete Guide
C++20 - The Complete Guide
About the Book
C++20 is the next evolution in modern C++ programming, which will be supported step-by-step by the latest version of gcc, clang, and Visual C++.
C++20 is a big step, maybe even larger than C++11.
It contains a couple of new key features (modules, concepts, ranges, corountines) plus several small but 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++20. 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 C++20 in practice.
Testimonials:
"C++20 scared me for a few years, and I am a C++ educator. After reading Nico's fantastic new book, I may still be afraid of C++20, but at least now I have a much deeper understanding of what it actually is I am afraid of. Leor Zolman
"I use this book as reference almost everyday." Selvakumar Jawahar
Buy early, pay less, free updates
Note that this book is published step-by-step. The first public version was published in June 2021. Since then, the contents grows with new chapters, examples, and caveats about the features of C++20 and I integrate all feedback I get for the pages already published.
The book is feature complete now.
Just minore details and copy editing is missing.
See cppstd20.com for a detailed list of all the topics covered.
As written, once you bought the ebook 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
#cpp20tcg
Bundles that include this book
Table of Contents
-
Preface
- An Experiment
- Acknowledgments
- Versions of This Book
-
About This Book
- What You Should Know Before Reading This Book
- Overall Structure of the Book
- How to Read This Book
-
The Way I Implement
- Initializations
- Error Terminology
- Code Simplifications
- The C++ Standards
- Example Code and Additional Information
- Feedback
-
1. Comparisons and Operator
<=>
-
1.1 Motivation for Operator
<=>
- 1.1.1 Defining Comparison Operators Before C++20
- 1.1.2 Defining Comparison Operators Since C++20
-
1.2 Defining and Using Comparisons
-
1.2.1 Using Operator
<=>
- 1.2.2 Comparison Category Types
-
1.2.3 Using Comparison Categories with
operator<=>
-
1.2.4 Calling Operator
<=>
Directly - 1.2.5 Dealing with Multiple Ordering Criteria
-
1.2.1 Using Operator
-
1.3 Defining
operator<=>
andoperator==
-
1.3.1 Defaulted
operator==
andoperator<=>
-
1.3.2 Defaulted
operator<=>
Implies Defaultedoperator==
-
1.3.3 Implementation of the Defaulted
operator<=>
-
1.3.1 Defaulted
- 1.4 Overload Resolution with Rewritten Expressions
-
1.5 Using Operator
<=>
in Generic Code-
1.5.1
compare_three_way
-
1.5.2 Algorithm
lexicographical_compare_three_way()
-
1.5.1
-
1.6 Compatibility Issues with the Comparison Operators
- 1.6.1 Delegating Free-Standing Comparison Operators
- 1.6.2 Inheritance with Protected Members
- 1.7 Afternotes
-
1.1 Motivation for Operator
-
2. Placeholder Types for Function Parameters
-
2.1
auto
for Parameters of Ordinary Functions-
2.1.1
auto
for Parameters of Member Functions
-
2.1.1
-
2.2 Using
auto
for Parameters in Practice-
2.2.1 Deferred Type Checks with
auto
-
2.2.2
auto
Functions versus Lambdas
-
2.2.1 Deferred Type Checks with
-
2.3
auto
for Parameters in Detail-
2.3.1 Basic Constraints for
auto
Parameters -
2.3.2 Combining Template and
auto
Parameters
-
2.3.1 Basic Constraints for
- 2.4 Afternotes
-
2.1
-
3. Concepts, Requirements, and Constraints
-
3.1 Motivating Example of Concepts and Requirements
- 3.1.1 Improving the Template Step by Step
- 3.1.2 A Complete Example with Concepts
-
3.2 Where Constraints and Concepts Can Be Used
- 3.2.1 Constraining Alias Templates
- 3.2.2 Constraining Variable Templates
- 3.2.3 Constraining Member Functions
- 3.2.4 Constraining Non-Type Template Parameters
-
3.3 Typical Applications of Concepts and Constraints in Practice
- 3.3.1 Using Concepts to Understand Code and Error Messages
- 3.3.2 Using Concepts to Disable Generic Code
- 3.3.3 Using Requirements to Call Different Functions
- 3.3.4 The Example as a Whole
- 3.3.5 Former Workarounds
-
3.4 Semantic Constraints
- 3.4.1 Examples of Semantic Constraints
-
3.5 Design Guidelines for Concepts
- 3.5.1 Concepts Should Group Requirements
- 3.5.2 Define Concepts with Care
- 3.5.3 Concepts versus Type Traits and Boolean Expressions
- 3.6 Afternotes
-
3.1 Motivating Example of Concepts and Requirements
-
4. Concepts, Requirements, and Constraints in Detail
- 4.1 Constraints
-
4.2
requires
Clauses-
4.2.1 Using
&&
and||
inrequires
Clauses
-
4.2.1 Using
- 4.3 Ad-hoc Boolean Expressions
-
4.4
requires
Expressions- 4.4.1 Simple Requirements
- 4.4.2 Type Requirements
- 4.4.3 Compound Requirements
- 4.4.4 Nested Requirements
-
4.5 Concepts in Detail
- 4.5.1 Defining Concepts
- 4.5.2 Special Abilities of Concepts
- 4.5.3 Concepts for Non-Type Template Parameters
- 4.6 Using Concepts as Type Constraints
-
4.7 Subsuming Constraints with Concepts
- 4.7.1 Indirect Subsumptions
- 4.7.2 Defining Commutative Concepts
-
5. Standard Concepts in Detail
-
5.1 Overview of All Standard Concepts
- 5.1.1 Header Files and Namespaces
- 5.1.2 Standard Concepts Subsume
-
5.2 Language-Related Concepts
- 5.2.1 Arithmetic Concepts
- 5.2.2 Object Concepts
- 5.2.3 Concepts for Relationships between Types
- 5.2.4 Comparison Concepts
-
5.3 Concepts for Iterators and Ranges
- 5.3.1 Concepts for Ranges and Views
- 5.3.2 Concepts for Pointer-Like Objects
- 5.3.3 Concepts for Iterators
- 5.3.4 Iterator Concepts for Algorithms
-
5.4 Concepts for Callables
- 5.4.1 Basic Concepts for Callables
- 5.4.2 Concepts for Callables Used by Iterators
-
5.5 Auxiliary Concepts
- 5.5.1 Concepts for Specific Type Attributes
- 5.5.2 Concepts for Incrementable Types
-
5.1 Overview of All Standard Concepts
-
6. Ranges and Views
-
6.1 A Tour of Ranges and Views Using Examples
- 6.1.1 Passing Containers to Algorithms as Ranges
- 6.1.2 Constraints and Utilities for Ranges
- 6.1.3 Views
- 6.1.4 Sentinels
- 6.1.5 Range Definitions with Sentinels and Counts
- 6.1.6 Projections
- 6.1.7 Utilities for Implementing Code for Ranges
- 6.1.8 Limitations and Drawbacks of Ranges
-
6.2 Borrowed Iterators and Ranges
- 6.2.1 Borrowed Iterators
- 6.2.2 Borrowed Ranges
-
6.3 Using Views
- 6.3.1 Views on Ranges
- 6.3.2 Lazy Evaluation
- 6.3.3 Caching in Views
- 6.3.4 Performance Issues with Filters
-
6.4 Views on Ranges That Are Destroyed or Modified
- 6.4.1 Lifetime Dependencies Between Views and Their Ranges
- 6.4.2 Views with Write Access
- 6.4.3 Views on Ranges That Change
- 6.4.4 Copying Views Might Change Behavior
-
6.5 Views and
const
- 6.5.1 Generic Code for Both Containers and Views
-
6.5.2 Views May Remove the Propagation of
const
- 6.5.3 Bringing Back Deep Constness to Views
- 6.6 Summary of All Container Idioms Broken By Views
- 6.7 Afternotes
-
6.1 A Tour of Ranges and Views Using Examples
-
7. Utilities for Ranges and Views
-
7.1 Key Utilities for Using Ranges as Views
-
7.1.1
std::views::all()
-
7.1.2
std::views::counted()
-
7.1.3
std::views::common()
-
7.1.1
- 7.2 New Iterator Categories
-
7.3 New Iterator and Sentinel Types
-
7.3.1
std::counted_iterator
-
7.3.2
std::common_iterator
-
7.3.3
std::default_sentinel
-
7.3.4
std::unreachable_sentinel
-
7.3.5
std::move_sentinel
-
7.3.1
-
7.4 New Functions for Dealing with Ranges
- 7.4.1 Functions for Dealing with the Elements of Ranges (and Arrays)
- 7.4.2 Functions for Dealing with Iterators
- 7.4.3 Functions for Swapping and Moving Elements/Values
- 7.4.4 Functions for Comparisons of Values
-
7.5 New Type Functions/Utilities for Dealing with Ranges
- 7.5.1 Generic Types of Ranges
- 7.5.2 Generic Types of Iterators
- 7.5.3 New Functional Types
- 7.5.4 Other New Types for Dealing with Iterators
-
7.6 Range Algorithms
- 7.6.1 Benefits and Restrictions for Range Algorithms
- 7.6.2 Algorithm Overview
-
7.1 Key Utilities for Using Ranges as Views
-
8. View Types in Detail
-
8.1 Overview of All Views
- 8.1.1 Overview of Wrapping and Generating Views
- 8.1.2 Overview of Adapting Views
-
8.2 Base Class and Namespace of Views
- 8.2.1 Base Class for Views
- 8.2.2 Why Range Adaptors/Factories Have Their Own Namespace
-
8.3 Source Views to External Elements
- 8.3.1 Subrange
- 8.3.2 Ref View
- 8.3.3 Owning View
- 8.3.4 Common View
-
8.4 Generating Views
- 8.4.1 Iota View
- 8.4.2 Single View
- 8.4.3 Empty View
- 8.4.4 IStream View
- 8.4.5 String View
- 8.4.6 Span
-
8.5 Filtering Views
- 8.5.1 Take View
- 8.5.2 Take-While View
- 8.5.3 Drop View
- 8.5.4 Drop-While View
- 8.5.5 Filter View
-
8.6 Transforming Views
- 8.6.1 Transform View
- 8.6.2 Elements View
- 8.6.3 Keys and Values View
-
8.7 Mutating Views
- 8.7.1 Reverse View
-
8.8 Views for Multiple Ranges
- 8.8.1 Split and Lazy-Split View
- 8.8.2 Join View
-
8.1 Overview of All Views
-
9. Spans
-
9.1 Using Spans
- 9.1.1 Fixed and Dynamic Extent
- 9.1.2 Example Using a Span with a Dynamic Extent
-
9.1.3 Example Using a Span with Non-
const
Elements - 9.1.4 Example Using a Span with Fixed Extent
- 9.1.5 Fixed vs. Dynamic Extent
- 9.2 Spans Considered Harmful
-
9.3 Design Aspects of Spans
- 9.3.1 Lifetime Dependencies of Spans
- 9.3.2 Performance of Spans
-
9.3.3
const
Correctness of Spans - 9.3.4 Using Spans as Parameters in Generic Code
-
9.4 Span Operations
- 9.4.1 Span Operations and Member Types Overview
- 9.4.2 Constructors
- 9.4.3 Operations for Sub-Spans
- 9.5 Afternotes
-
9.1 Using Spans
-
10. Formatted Output
-
10.1 Formatted Output by Example
-
10.1.1 Using
std::format()
-
10.1.2 Using
std::format_to_n()
-
10.1.3 Using
std::format_to()
-
10.1.4 Using
std::formatted_size()
-
10.1.1 Using
-
10.2 Performance of the Formatting Library
-
10.2.1 Using
std::vformat()
andvformat_to()
-
10.2.1 Using
-
10.3 Formatted Output in Detail
- 10.3.1 General Format of Format Strings
- 10.3.2 Standard Format Specifiers
- 10.3.3 Width, Precision, and Fill Characters
- 10.3.4 Format/Type Specifiers
- 10.4 Internationalization
- 10.5 Error Handling
-
10.6 User-Defined Formatted Output
- 10.6.1 Basic Formatter API
- 10.6.2 Improved Parsing
- 10.6.3 Using Standard Formatters for User-Defined Formatters
- 10.6.4 Using Standard Formatters for Strings
- 10.7 Afternotes
-
10.1 Formatted Output by Example
-
11. Dates and Timezones for
<chrono>
-
11.1 Overview by Example
- 11.1.1 Scheduling a Meeting on the 5th of Every Month
- 11.1.2 Scheduling a Meeting on the Last Day of Every Month
- 11.1.3 Scheduling a Meeting Every First Monday
- 11.1.4 Using Different Timezones
- 11.2 Basic Chrono Concepts and Terminology
-
11.3 Basic Chrono Extensions with C++20
- 11.3.1 Duration Types
- 11.3.2 Clocks
- 11.3.3 Timepoint Types
- 11.3.4 Calendrical Types
-
11.3.5 Time Type
hh_mm_ss
- 11.3.6 Hours Utilities
-
11.4 I/O with Chrono Types
- 11.4.1 Default Output Formats
- 11.4.2 Formatted Output
- 11.4.3 Locale-Dependent Output
- 11.4.4 Formatted Input
-
11.5 Using the Chrono Extensions in Practice
- 11.5.1 Invalid Dates
-
11.5.2 Dealing with
months
andyears
- 11.5.3 Parsing Timepoints and Durations
-
11.6 Timezones
- 11.6.1 Characteristics of Timezones
- 11.6.2 The IANA Timezone Database
- 11.6.3 Using Timezones
- 11.6.4 Dealing with Timezone Abbreviations
- 11.6.5 Custom Timezones
-
11.7 Clocks in Detail
- 11.7.1 Clocks with a Specified Epoch
-
11.7.2 The Pseudo Clock
local_t
- 11.7.3 Dealing with Leap Seconds
- 11.7.4 Conversions between Clocks
- 11.7.5 Dealing with the File Clock
- 11.8 Other New Chrono Features
- 11.9 Afternotes
-
11.1 Overview by Example
-
12.
std::jthread
and Stop Tokens-
12.1 Motivation for
std::jthread
-
12.1.1 The Problem of
std::thread
-
12.1.2 Using
std::jthread
- 12.1.3 Stop Tokens and Stop Callbacks
- 12.1.4 Stop Tokens and Condition Variables
-
12.1.1 The Problem of
-
12.2 Stop Sources and Stop Tokens
- 12.2.1 Stop Sources and Stop Tokens in Detail
- 12.2.2 Using Stop Callbacks
- 12.2.3 Constraints and Guarantees of Stop Tokens
-
12.3
std::jthread
in Detail-
12.3.1 Using Stop Tokens with
std::jthread
-
12.3.1 Using Stop Tokens with
- 12.4 Afternotes
-
12.1 Motivation for
-
13. Concurrency Features
-
13.1 Thread Synchronization with Latches and Barriers
- 13.1.1 Latches
- 13.1.2 Barriers
-
13.2 Semaphores
- 13.2.1 Example of Using Counting Semaphores
- 13.2.2 Example of Using Binary Semaphores
-
13.3 Extensions for Atomic Types
-
13.3.1 Atomic References with
std::atomic_ref<>
- 13.3.2 Atomic Shared Pointers
- 13.3.3 Atomic Floating-Point Types
- 13.3.4 Thread Synchronization with Atomic Types
-
13.3.5 Extensions for
std::atomic_flag
-
13.3.1 Atomic References with
-
13.4 Synchronized Output Streams
- 13.4.1 Motivation for Synchronized Output Streams
- 13.4.2 Using Synchronized Output Streams
- 13.4.3 Using Synchronized Output Streams for Files
- 13.4.4 Using Synchronized Output Streams as Output Streams
- 13.4.5 Synchronized Output Streams in Practice
- 13.5 Afternotes
-
13.1 Thread Synchronization with Latches and Barriers
-
14. Coroutines
- 14.1 What Are Coroutines?
-
14.2 A First Coroutine Example
- 14.2.1 Defining the Coroutine
- 14.2.2 Using the Coroutine
- 14.2.3 Lifetime Issues with Call-by-Reference
- 14.2.4 Coroutines Calling Coroutines
- 14.2.5 Implementing the Coroutine Interface
- 14.2.6 Bootstrapping Interface, Handle, and Promise
- 14.2.7 Memory Management
-
14.3 Coroutines That Yield or Return Values
-
14.3.1 Using
co_yield
-
14.3.2 Using
co_return
-
14.3.1 Using
-
14.4 Coroutine Awaitables and Awaiters
- 14.4.1 Awaiters
- 14.4.2 Standard Awaiters
- 14.4.3 Resuming Sub-Coroutines
- 14.4.4 Passing Values From Suspension Back to the Coroutine
- 14.5 Afternotes
-
15. Coroutines in Detail
-
15.1 Coroutine Constraints
- 15.1.1 Coroutine Lambdas
-
15.2 The Coroutine Frame and the Promises
- 15.2.1 How Coroutine Interfaces, Promises, and Awaitables Interact
-
15.3 Coroutine Promises in Detail
- 15.3.1 Mandatory Promise Operations
- 15.3.2 Promise Operations to Return or Yield Values
- 15.3.3 Optional Promise Operations
-
15.4 Coroutine Handles in Detail
-
15.4.1
std::coroutine_handle<void>
-
15.4.1
- 15.5 Exceptions in Coroutines
-
15.6 Allocating Memory for the Coroutine Frame
- 15.6.1 How Coroutines Allocate Memory
- 15.6.2 Avoiding Heap Memory Allocation
-
15.6.3
get_return_object_on_allocation_failure()
-
15.7
co_await
and Awaiters in Detail- 15.7.1 Details of the Awaiter Interface
-
15.7.2 Letting
co_await
Update Running Coroutines - 15.7.3 Symmetric Transfer with Awaiters for Continuation
-
15.8 Other Ways of Dealing with
co_await
-
15.8.1
await_transform()
-
15.8.2
operator co_await()
-
15.8.1
-
15.9 Concurrent Use of Coroutines
-
15.9.1
co_await
Coroutines - 15.9.2 A Thread Pool for Coroutine Tasks
- 15.9.3 What C++ Libraries Will Provide After C++20
-
15.9.1
- 15.10 Coroutine Traits
-
15.1 Coroutine Constraints
-
16. Modules
-
16.1 Motivation for Modules Using a First Example
- 16.1.1 Implementing and Exporting a Module
- 16.1.2 Compiling Module Units
- 16.1.3 Importing and Using a Module
- 16.1.4 Reachable versus Visible
- 16.1.5 Modules and Namespaces
-
16.2 Modules with Multiple Files
- 16.2.1 Module Units
- 16.2.2 Using Implementation Units
- 16.2.3 Internal Partitions
- 16.2.4 Interface Partitions
- 16.2.5 Summary of Splitting Modules into Different Files
-
16.3 Dealing with Modules in Practice
- 16.3.1 Dealing with Module Files with Different Compilers
- 16.3.2 Dealing with Header Files
-
16.4 Modules in Detail
- 16.4.1 Private Module Fragments
- 16.4.2 Module Declaration and Export in Detail
- 16.4.3 Umbrella Modules
- 16.4.4 Module Import in Detail
- 16.4.5 Reachable versus Visible Symbols in Detail
- 16.5 Afternotes
-
16.1 Motivation for Modules Using a First Example
-
17. Lambda Extensions
-
17.1 Generic Lambdas with Template Parameters
- 17.1.1 Using Template Parameters for Generic Lambdas in Practice
- 17.1.2 Explicit Specification of Lambda Template Parameters
- 17.2 Calling the Default Constructor of Lambdas
- 17.3 Lambdas as Non-Type Template Parameters
-
17.4
consteval
Lambdas -
17.5 Changes for Capturing
-
17.5.1 Capturing
this
and*this
- 17.5.2 Capturing Structured Bindings
- 17.5.3 Capturing Parameter Packs of Variadic Templates
- 17.5.4 Lambdas as Coroutines
-
17.5.1 Capturing
- 17.6 Afternotes
-
17.1 Generic Lambdas with Template Parameters
-
18. Compile-Time Computing
-
18.1 Keyword
constinit
-
18.1.1 Using
constinit
in Practice -
18.1.2 How
constinit
Solves the Static Initialization Order Fiasco
-
18.1.1 Using
-
18.2 Keyword
consteval
-
18.2.1 A First
consteval
Example -
18.2.2
constexpr
versusconsteval
-
18.2.3 Using
consteval
in Practice - 18.2.4 Compile-Time Value versus Compile-Time Context
-
18.2.1 A First
-
18.3 Relaxed Constraints for
constexpr
Functions -
18.4
std::is_constant_evaluated()
-
18.4.1
std::is_constant_evaluated()
in Detail
-
18.4.1
-
18.5 Using Heap Memory, Vectors, and Strings at Compile Time
- 18.5.1 Using Vectors at Compile Time
- 18.5.2 Returning a Collection at Compile Time
- 18.5.3 Using Strings at Compile Time
-
18.6 Other
constexpr
Extensions-
18.6.1
constexpr
Language Extensions -
18.6.2
constexpr
Library Extensions
-
18.6.1
- 18.7 Afternotes
-
18.1 Keyword
-
19. Non-Type Template Parameter (NTTP) Extensions
-
19.1 New Types for Non-Type Template Parameters
- 19.1.1 Floating-Point Values as Non-Type Template Parameters
- 19.1.2 Objects as Non-Type Template Parameters
- 19.1.3 Lambdas as Non-Type Template Parameters
- 19.2 Afternotes
-
19.1 New Types for Non-Type Template Parameters
-
20. New Type Traits
-
20.1 New Type Traits for Type Classification
-
20.1.1
is_bounded_array_v<>
andis_unbounded_array_v
-
20.1.1
-
20.2 New Type Traits for Type Inspection
-
20.2.1
is_nothrow_convertible_v<>
-
20.2.1
-
20.3 New Type Traits for Type Conversion
-
20.3.1
remove_cvref_t<>
-
20.3.2
unwrap_reference<>
andunwrap_ref_decay_t
-
20.3.3
common_reference<>_t
-
20.3.4
type_identity_t<>
-
20.3.1
-
20.4 New Type Traits for Iterators
-
20.4.1
iter_difference_t<>
-
20.4.2
iter_value_t<>
-
20.4.3
iter_reference_t<>
anditer_rvalue_reference_t<>
-
20.4.1
-
20.5 Type Traits and Functions for Layout Compatibility
-
20.5.1
is_layout_compatible_v<>
-
20.5.2
is_pointer_interconvertible_base_of_v<>
-
20.5.3
is_corresponding_member()
-
20.5.4
is_pointer_interconvertible_with_class()
-
20.5.1
- 20.6 Afternotes
-
20.1 New Type Traits for Type Classification
-
21. Small Improvements for the Core Language
-
21.1 Range-Based
for
Loop with Initialization -
21.2
using
for Enumeration Values - 21.3 Delegating Enumeration Types to Different Scopes
-
21.4 New Character Type
char8_t
-
21.4.1 Changes in the C++ Standard Library for
char8_t
- 21.4.2 Broken Backward Compatibility
-
21.4.1 Changes in the C++ Standard Library for
-
21.5 Improvements for Aggregates
- 21.5.1 Designated Initializers
- 21.5.2 Aggregate Initialization with Parentheses
- 21.5.3 Definition of Aggregates
-
21.6 New Attributes and Attribute Features
-
21.6.1 Attributes
[[likely]]
and[[unlikely]]
-
21.6.2 Attribute
[[no_unique_address]]
-
21.6.3 Attribute
[[nodiscard]]
with Parameter
-
21.6.1 Attributes
- 21.7 Feature Test Macros
- 21.8 Afternotes
-
21.1 Range-Based
-
22. Small Improvements for Generic Programming
-
22.1 Implicit
typename
for Type Members of Template Parameters-
22.1.1 Rules for Implicit
typename
in Detail
-
22.1.1 Rules for Implicit
-
22.2 Improvements for Aggregates in Generic Code
- 22.2.1 Class Template Argument Deduction (CTAD) for Aggregates
-
22.3 Conditional
explicit
-
22.3.1 Conditional
explicit
in the Standard Library
-
22.3.1 Conditional
- 22.4 Afternotes
-
22.1 Implicit
-
23. Small Improvements for the C++ Standard Library
-
23.1 Updates for String Types
-
23.1.1 String Members
starts_with()
andends_with()
-
23.1.2 Restricted String Member
reserve()
-
23.1.1 String Members
-
23.2
std::source_location
-
23.3 Safe Comparisons of Integral Values and Sizes
- 23.3.1 Safe Comparisons of Integral Values
-
23.3.2
ssize()
- 23.4 Mathematical Constants
-
23.5 Utilities for Dealing with Bits
- 23.5.1 Bit Operations
-
23.5.2
std::bit_cast<>()
-
23.5.3
std::endian
-
23.6
<version>
-
23.7 Extensions for Algorithms
- 23.7.1 Range Support
- 23.7.2 New Algorithms
-
23.7.3
unseq
Execution Policy for Algorithms
- 23.8 Afternotes
-
23.1 Updates for String Types
-
24. Deprecated and Removed Features
- 24.1 Deprecated and Removed Core Language Features
-
24.2 Deprecated and Removed Library Features
- 24.2.1 Deprecated Library Features
- 24.2.2 Removed Library Features
- 24.3 Afternotes
-
Glossary
-
A
- aggregate
- argument-dependent lookup (ADL)
-
C
- class template argument deduction (CTAD)
-
F
- forwarding reference
- full specialization
- function object (functor)
-
G
- glvalue
-
I
- incomplete type
-
L
- lvalue
-
P
- partial specialization
- predicate
- prvalue
-
R
- resource acquisition is initialization (RAII)
- regular type
- rvalue
-
S
- semiregular type
- substitution failure is not an error (SFINAE)
- small string optimization (SSO)
- stateless
- standard template library (STL)
-
U
- universal reference
-
V
- value category
- variable template
- variadic template
-
X
- xvalue
-
A
- Notes
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