Punctuation

 

C++

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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

 

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
Inline assembly	History of C++

 

Basic Concepts

Comments

ASCII

Punctuation

Names and identifiers

Types

Fundamental types

Objects

Scope

Object lifetime

Storage duration and linkage

Definitions and ODR

Name lookup

Qualified name lookup

Unqualified name lookup

The as-if rule

Undefined behavior

Memory model

Multi-threaded executions and data races (C++11)

Character sets and encodings

Phases of translation

The main function

Modules (C++20)

Contracts (C++26)

 

These are the punctuation symbols in C++. The meaning of each symbol is detailed in the linked pages.

Preprocessing operators

Preprocessing operators are recognized by preprocessors.

# (including %:)

• Introduce a preprocessing directive.
• The preprocessing operator for stringification.

##(including %:%:)

• The preprocessing operator for token pasting.

Single-character operators and punctuators

{ and } (including <% and %>)

• In a class definition, delimit the member specification.
• In an enumeration definition, delimit the enumerator list.
• Delimit a compound statement. The compound statement may be part of

• a function definition
• a try block

a lambda expression

(since C++11)

• Part of the aggregate initialization(until C++11)list-initialization(since C++11) syntax of an initializer.
• In a namespace definition, delimit the namespace body.
• In a language linkage specification, delimit the declarations.

In a requires expression, delimit the requirements. In a compound requirement, delimit the expression. In an export declaration, delimit the declarations.

(since C++20)

[ and ] (including <: and :>)

• Subscript operator; part of operator[] in operator overloading.
• Part of array declarator in a declaration or a type-id (e.g. in a new expression).
• Part of new[] operator in operator overloading (allocation function).
• Part of delete[] operator in delete expression and operator overloading (deallocation function).

In a lambda expression, delimit the captures. In an attribute specifier, delimit the attributes.	(since C++11)
In a structured binding declaration, delimit the identifier list.	(since C++17)
In a pack indexing, delimit converted constant expression representing an index.	(since C++26)

( and )

• In an expression, indicate grouping.
• Function call operator; part of operator() in operator overloading.
• In a function-style type cast, delimit the expression/initializers.
• In a static_cast, const_cast, reinterpret_cast, or dynamic_cast, delimit the expression.
• Delimit the operand of the following operators:

• typeid
• sizeof

sizeof... alignof noexcept

(since C++11)

• In a placement new expression, delimit the placement arguments.
• In a new expression, optionally delimit the type-id.
• In a new expression, delimit the initializers.
• In a C-style cast, delimit the type-id.
• In a declaration or a type-id, indicate grouping.
• Delimit the parameter list in

• a function declarator (in a declaration or a type-id)

a lambda expression	(since C++11)
a user-defined deduction guide	(since C++17)
a requires expression	(since C++20)

• Part of the direct-initialization syntax of an initializer.
• In an asm declaration, delimit the string literal.
• In a member initializer list, delimit the initializers to a base or member.
• Delimit the controlling clause of a selection statement or iteration statement, including:

• if (except consteval if)(since C++23)
• switch
• while
• do-while
• for

range-based for

(since C++11)

• In a handler, delimit the parameter declaration.
• In a function-like macro definition, delimit the macro parameters.
• In a function-like macro invocation, delimit the macro arguments or prevent commas from being interpreted as argument separators.
• Part of a defined, __has_include(since C++17), __has_cpp_attribute(since C++20) preprocessing operator.

In a static_assert declaration, delimit the operands. Delimit the operand of the following specifiers: decltype noexcept alignas explicit (since C++20) In an attribute, delimit the attribute arguments.	(since C++11)
Part of decltype(auto) specifier.	(since C++14)
Delimit a fold expression.	(since C++17)
Part of __VA_OPT__ replacement in a variadic macro definition.	(since C++20)

;

• Indicate the end of

• a statement
• a declaration or member declaration

a module declaration, import declaration, global module fragment introducer, or private module fragment introducer a requirement

(since C++20)

• Separate the condition and statement of a for statement.

:

• Part of conditional operator.
• Part of label declaration.
• In the base-clause of a class definition, introduce the base class.
• Part of access specifier in member specification.
• In a bit-field member declaration, introduce the width.
• In a constructor definition, introduce the member initializer list.

In a range-based for statement, separate the item-declaration and the range-initializer. In the enum-base of an enumeration declaration, introduce the underlying type.	(since C++11)
In an attribute specifier, separate the attribute-namespace and the attribute-list.	(since C++17)
In a module declaration or import declaration of module partition, introduce the module partition name. Part of a private module fragment introducer (module :private;).	(since C++20)

?

• Part of conditional operator.

.

• Member access operator.

In aggregate initialization, introduce a designator. Part of module name or module partition name.

(since C++20)

~ (including compl)

• Unary complement operator (a.k.a. bitwise not operator); part of operator~ in operator overloading.
• Part of an identifier expression to name a destructor or pseudo-destructor.

! (including not)

• Logical not operator; part of operator! in operator overloading.

Part of consteval if statement.

(since C++23)

+

• Unary plus operator; part of operator+ in operator overloading.
• Binary plus operator; part of operator+ in operator overloading.

-

• Unary minus operator; part of operator- in operator overloading.
• Binary minus operator; part of operator- in operator overloading.

*

• Indirection operator; part of operator* in operator overloading.
• Multiplication operator; part of operator* in operator overloading.
• Pointer operator or part of pointer-to-member operator in a declarator or in a type-id.

Part of *this in a lambda capture list, to capture the current object by copy.

(since C++17)

/

• Division operator; part of operator/ in operator overloading.

%

• Modulo operator; part of operator% in operator overloading.

^ (including xor)

• Bitwise xor operator; part of operator^ in operator overloading.

& (including bitand)

• Address-of operator; part of operator& in operator overloading.
• Bitwise and operator; part of operator& in operator overloading.
• Lvalue-reference operator in a declarator or in a type-id.

In a lambda capture, indicate by-reference capture. Ref-qualifier in member function declaration.

(since C++11)

| (including bitor)

• Bitwise or operator; part of operator| in operator overloading.

=

• Simple assignment operator; part of operator= in operator overloading, which might be a special member function (copy assignment operatoror move assignment operator(since C++11)).
• Part of the copy-initialization and aggregate initialization(until C++11)copy-list-initialization(since C++11) syntax of an initializer.
• In a function declaration, introduce a default argument.
• In a template parameter list, introduce a default template argument.
• In a namespace alias definition, separate the alias and the aliased namespace.
• In an enum definition, introduce the value of enumerator.
• Part of pure-specifier in a pure virtual function declaration.

Capture default in lambda capture, to indicate by-copy capture. Part of defaulted definition (=default;) or deleted definition (=delete;) in function definition. In a type alias declaration, separate the alias and the aliased type.	(since C++11)
In a concept definition, separate the concept name and the constraint expression.	(since C++20)

<

• Less-than operator; part of operator< in operator overloading.
• In a static_cast, const_cast, reinterpret_cast, or dynamic_cast, introduce the type-id.
• Introduce a template argument list.
• Introduce a template parameter list in

• a template declaration
• a partial specialization

a lambda expression

(since C++20)

• Part of template<> in template specialization declaration.
• Introduce a header name in

• a #include directive

a __has_include preprocessing expression	(since C++17)
an import declaration	(since C++20)

>

• Greater-than operator; part of operator> in operator overloading.
• static_cast, const_cast, reinterpret_cast, or dynamic_cast, indicate the end of type-id.
• Indicate the end of a template argument list.
• Indicate the end of a template parameter list in

• a template declaration
• a partial specialization

a lambda expression

(since C++20)

• Part of template<> in template specialization declaration.
• Indicate the end of a header name in

• a #include directive

a __has_include preprocessing expression	(since C++17)
an import declaration	(since C++20)

,

• Comma operator; part of operator, in operator overloading.
• List separator in

• the declarator list in a declaration
• initializer list in initialization
• the placement argument list in a placement new
• the argument list in a function call expression
• the enumerator list in an enum declaration
• the base class list in a class declaration
• the member initializer list in a constructor definition
• a function parameter list
• a template parameter list
• a template argument list

a lambda capture list an attribute list	(since C++11)
the declarator list in a using-declaration the identifier list in a structured binding declaration	(since C++17)
the argument list in a multi-argument subscript expression	(since C++23)

• the macro parameter list in a function-like macro definition
• the macro argument list in a function-like macro invocation, unless found between the parentheses of an argument

In a static_assert declaration, separate the arguments.

(since C++11)

Multi-character operators and punctuators

...

• In the parameter list of a function declaratoror lambda expression(since C++11)or user-defined deduction guide(since C++17), signify a variadic function.
• In a handler, signify catch-all handler.

In a macro definition, signify a variadic macro. Indicate pack declaration and expansion.	(since C++11)
In pack indexing expression and specifier.	(since C++26)

::

• Scope resolution operator in

• a qualified name
• a pointer-to-member declaration
• a new or delete expression, to indicate that only global allocation or deallocation functions are looked up

In an attribute, indicate attribute scope.	(since C++11)
Part of nested namespace definition.	(since C++17)

.*

• Pointer-to-member access operator.

->

• Member access operator; part of operator-> in operator overloading.

In a function declarator or lambda expression, introduce the trailing return type.	(since C++11)
In a user-defined deduction guide, introduce the result type.	(since C++17)
In a compound requirement, introduce the return type requirement.	(since C++20)

->*

• Pointer-to-member access operator; part of operator->* in operator overloading.

+=

• Compound assignment operator; part of operator+= in operator overloading.

-=

• Compound assignment operator; part of operator-= in operator overloading.

*=

• Compound assignment operator; part of operator*= in operator overloading.

/=

• Compound assignment operator; part of operator/= in operator overloading.

%=

• Compound assignment operator; part of operator%= in operator overloading.

^= (including xor_eq)

• Compound assignment operator; part of operator^= in operator overloading.

&= (including and_eq)

• Compound assignment operator; part of operator&= in operator overloading.

|= (including or_eq)

• Compound assignment operator; part of operator|= in operator overloading.

==

• Equality operator; part of operator== in operator overloading.

!= (including not_eq)

• Inequality operator; part of operator!= in operator overloading.

<=

• Less-than-or-equal-to operator; part of operator<= in operator overloading.

>=

• Greater-than-or-equal-to operator; part of operator>= in operator overloading.

<=> Three-way comparison (spaceship) operator; part of operator<=> in operator overloading.

(since C++20)

&& (including and)

• Logical and operator; part of operator&& in operator overloading.

Rvalue-reference operator in a declarator or in a type-id. Ref-qualifier in member function declaration.

(since C++11)

|| (including or)

• Logical or operator; part of operator|| in operator overloading.

<<

• Bitwise shift operator; part of operator<< in operator overloading (bitwise operator or stream insertion operator).

>>

• Bitwise shift operator; part of operator>> in operator overloading (bitwise operator or stream extraction operator).

<<=

• Compound assignment operator; part of operator<<= in operator overloading.

>>=

• Compound assignment operator; part of operator>>= in operator overloading.

++

• Increment operator; part of operator++ in operator overloading.

--

• Decrement operator; part of operator-- in operator overloading.

References

• C++23 standard (ISO/IEC 14882:2024):

• 5.12 Operators and punctuators [lex.operators]

• C++20 standard (ISO/IEC 14882:2020):

• 5.12 Operators and punctuators [lex.operators]

• C++17 standard (ISO/IEC 14882:2017):

• 5.12 Operators and punctuators [lex.operators]

• C++14 standard (ISO/IEC 14882:2014):

• 2.13 Operators and punctuators [lex.operators]

• C++11 standard (ISO/IEC 14882:2011):

• 2.13 Operators and punctuators [lex.operators]

• C++03 standard (ISO/IEC 14882:2003):

• 2.12 Operators and punctuators [lex.operators]

• C++98 standard (ISO/IEC 14882:1998):

• 2.12 Operators and punctuators [lex.operators]

See also

Alternative representations	alternative spellings for certain operators
C documentation for Punctuation