C++ keyword:`constexpr`(since C++11)

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Compiler support
Freestanding and hosted
Language
Standard library
Standard library headers
Named requirements
Feature test macros(C++20)
Language support library
Concepts library(C++20)
Diagnostics library
Memory management library
Metaprogramming library(C++11)
General utilities library
Containers library
Iterators library
Ranges library(C++20)
Algorithms library
Strings library
Text processing library
Numerics library
Date and time library
Input/output library
Filesystem library(C++17)
Concurrency support library(C++11)
Execution control library(C++26)
Technical specifications
Symbols index
External libraries

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C++ language

General topics

Preprocessor
Comments

Keywords
Escape sequences

Flow control

Conditional execution statements

if

switch

Iteration statements (loops)

`for`
range-`for`(C++11)

`while`
`do-while`

Jump statements

continue -break

goto -return

Functions

Function declaration

Lambda function expression

inline specifier

Dynamic exception specifications(until C++17*)

noexcept specifier(C++11)

Exceptions

`throw`-expression
`try` block


`catch` handler

Namespaces

Namespace declaration

Namespace aliases

Types

Fundamental types
Enumeration types
Function types

Class/struct types
Union types

Specifiers

`const`/`volatile`
`decltype`(C++11)
`auto`(C++11)

`constexpr`(C++11)
`consteval`(C++20)
`constinit`(C++20)

Storage duration specifiers

Initialization

Default-initialization
Value-initialization
Zero-initialization
Copy-initialization
Direct-initialization

Aggregate initialization
List-initialization(C++11)
Constant initialization
Reference initialization

Expressions

Value categories
Order of evaluation

Operators
Operator precedence

Alternative representations

Literals

Boolean -Integer -Floating-point

Character -String -nullptr(C++11)

User-defined(C++11)

Utilities

Attributes(C++11)

Types

typedef declaration

Type alias declaration(C++11)

Casts

Implicit conversions
`static_cast`
`const_cast`

Explicit conversions
`dynamic_cast`
`reinterpret_cast`

Memory allocation

new expression

delete expression

Classes

Class declaration
Constructors
`this` pointer

Access specifiers
`friend` specifier

Class-specific function properties

Virtual function
`override` specifier(C++11)
`final` specifier(C++11)

`explicit`(C++11)
`static`

Special member functions

Default constructor
Copy constructor
Move constructor(C++11)

Copy assignment
Move assignment(C++11)
Destructor

Templates

Class template
Function template

Template specialization
Parameter packs(C++11)

Miscellaneous

alignas (C++11)
alignof (C++11)
and
and_eq
asm
auto (*)
bitand
bitor
bool
break
case
catch
char
char8_t (C++20)
char16_t (C++11)
char32_t (C++11)
class
compl
concept (C++20)
const
consteval (C++20)
constexpr (C++11)
constinit (C++20)
const_cast
continue
contract_assert (C++26)
co_await (C++20)
co_return (C++20)
co_yield (C++20)
decltype (C++11)
default

delete
do
double
dynamic_cast
else
enum
explicit
export
extern
false
float
for
friend
goto
if
inline
int
long
mutable
namespace
new
noexcept (C++11)
not
not_eq
nullptr (C++11)
operator
or
or_eq
private
protected
public

register
reinterpret_cast
requires (C++20)
return
short
signed
sizeof (*)
static
static_assert (C++11)
static_cast
struct
switch
template
this
thread_local (C++11)
throw
true
try
typedef
typeid
typename
union
unsigned
using
virtual
void
volatile
wchar_t
while
xor
xor_eq

Identifiers with special meaning