C++ language

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C++ Standard Library
Language Utilities library Strings library Containers library Algorithms library Iterators library Numerics library Input/output library Localizations library Regular expressions library (C++11) Atomic operations library (C++11) Thread support library (C++11)
C++ language
General topics Preprocessor Comments Keywords ASCII chart Escape sequences History of C++ Flow control Conditional execution statements if statement switch statement Iteration statements for loop range-for loop (C++11) while loop do-while loop Jump statements continue statement break statement goto statement return statement Functions function declaration lambda function declaration function template inline specifier exception specifications (deprecated) noexcept specifier (C++11) Exceptions throw expression try-catch block Namespaces namespace declaration namespace aliases Types fundamental types compound types enumeration types union types function types decltype specifier (C++11) Specifiers cv specifiers storage duration specifiers constexpr specifier (C++11) auto specifier (C++11) alignas specifier (C++11) Literals integer literals character literals floating-point literals string literals boolean literals nullptr (C++11) user-defined (C++11) Expressions value categories order of evaluation operators operator precedence alternative representations Utilities Types typedef declaration type alias declaration (C++11) attributes (C++11) Casts implicit conversions const_cast conversion static_cast conversion dynamic_cast conversion reinterpret_cast conversion Memory allocation new expression delete expression Classes class declaration this pointer access specifiers friend specifier initializer lists 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) assignment operator move operator (C++11) destructor Templates class template function template template specialization parameter packs (C++11) Miscellaneous Inline assembly

This is a brief reference of available C++ constructs.

Contents 1 General topics 1.1 Preprocessor 1.2 Comments 1.3 Keywords 1.4 ASCII chart 1.5 Escape sequences 1.6 History of C++ 2 Flow control 2.1 Conditional execution statements 2.2 Iteration statements 2.3 Jump statements 3 Functions 4 Exceptions 5 Namespaces 6 Types 6.1 Specifiers 6.2 Literals 6.3 Expressions 6.4 Utilities 7 Classes 7.1 Class-specific function properties 7.2 Special member functions 8 Templates 9 Miscellaneous

[edit] General topics

[edit] Preprocessor

[edit] Comments

[edit] Keywords

[edit] ASCII chart

[edit] Escape sequences

[edit] History of C++

[edit] Flow control

[edit] Conditional execution statements

Different code paths are executed according to the value of given expression

• if executes code conditionally
• switch executes code according to the value of an integral argument

[edit] Iteration statements

The same code is executed several times

• for executes loop
• range-for executes loop over a range (since C++11)
• while executes loop, checking condition before each iteration
• do-while executes loop, checking condition after each iteration

[edit] Jump statements

Continue execution at a different location

• continue skips the remaining part of the enclosing loop body
• break terminates the enclosing loop
• goto continues execution in another location
• return terminates execution of the enclosing function

[edit] Functions

The same code can be reused at different locations in the program

• function declaration declares a function
• lambda function declaration declares a lambda function
• function template declares a function template
• inline specifier hints the compiler to insert a function's body directly into the calling code
• exception specifications enforces the function to throw only specific exceptions or not to throw at all (deprecated)
• noexcept specifier enforces the function not to throw any exceptions (since C++11)

[edit] Exceptions

Exceptions are a more robust way to signal error condition than function return codes or global error variables

• throw expression signals an error and transfers control to error handler
• try-catch block catches exceptions originating from specific block of code

[edit] Namespaces

Namespaces provide a way to prevent name clashes in large projects

• namespace declaration
• namespace aliases

[edit] Types

• fundamental types defines basic character, integer and floating point types
• compound types defines types, holding several data members (essentially the same as class)
• enumeration types defines types, that are able to hold only one of the specified values
• union types defines types, that can hold data in several representations
• function types define function call signatures, that is the types of arguments and the return type
• decltype specifier defines a type, equivalent to the type of an expression (since C++11)

[edit] Specifiers

• cv specifiers specifies constness and volatility of a type
• storage duration specifiers specifies storage duration of a type
• constexpr specifier specifies that the value of a variable or function can be computed at compile time (since C++11)
• auto specifier specifies that the actual type shall be defined from the expression, assigned to the variable (since C++11)
• alignas specifier specifies that the storage for the variable should be aligned by specific amount (since C++11)

[edit] Literals

Literals are the tokens of a C++ program that represent constant values, embedded in the source code.

• integer literals are decimal, octal, or hexadecimal numbers of integer type.
• character literals are individual characters of type char, char16_t, char32_t, or wchar_t.
• floating-point literals are values of type float, double, or long double
• string literals are sequences of characters, which may be narrow, multibyte, or wide.
• boolean literals are values of type bool, that is true and false
• nullptr is the pointer literal which specifies a null pointer value (since C++11)
• user-defined literals are constant values of user-specified type (since C++11)

[edit] Expressions

An expression is a sequence of operators and operands that specifies a computation. An expression can result in a value and can cause side effects.

• value categories (lvalue, rvalue, glvalue, prvalue, xvalue) classify expressions by their values.
• order of evaluation of arguments and subexpressions specified the order in which intermediate results are obtained.
• operators allow the use of syntax commonly found in mathematics

Common operators
assignment	increment decrement	arithmetic	logical	comparison	member access	other
a = b a = rvalue a += b a -= b a *= b a /= b a %= b a &= b a |= b a ^= b a <<= b a >>= b	++a --a a++ a--	+a -a a + b a - b a * b a / b a % b ~a a & b a | b a ^ b a << b a >> b	!a a && b a || b	a == b a != b a < b a > b a <= b a >= b	a[b] *a &a a->b a.b a->*b a.*b	a(...) a, b (type) a ? :
Special operators
static_cast converts one type to another compatible type dynamic_cast converts virtual base class to derived class const_cast converts type to compatible type with different cv qualifiers reinterpret_cast converts type to incompatible type new allocates memory delete deallocates memory sizeof queries the size of a type sizeof... queries the size of a parameter pack (since C++11) typeid queries the type information of a type noexcept checks if an expression can throw an exception (since C++11) alignof queries alignment requirements of a type (since C++11)

• operator precedence the order in which operators are bound to their arguments
• alternative representations alternative spellings for some of the operators

[edit] Utilities

Types

• typedef declaration creates a synonym for a type
• type alias declaration creates a synonym for a type
• attributes defines additional information about variable (since C++11)

Casts

• standard conversions implicit conversions from one type to another
• const_cast conversion
• static_cast conversion
• dynamic_cast conversion
• reinterpret_cast conversion

Memory allocation

• new expression allocates memory dynamically
• delete expression deallocates memory dynamically

[edit] Classes

Classes provide the concept of object-oriented programming in C++

• class declaration
• this pointer links to the current instance of a class in member methods
• access specifiers
• friend specifier grants access privileges to private/protected parts for non-member classes or functions
• initializer lists

[edit] Class-specific function properties

• virtual function specifier declares that a function is virtual.
• override specifier declares that a virtual function overrides another virtual function.(since C++11)
• final specifier declares that a virtual function can not be overridden in a inheriting class.(since C++11)
• explicit function specifier declares that a constructor or conversion operator can not be used in implicit conversions (since C++11)
• static function specifier declares that a function does not use class instance-specific data.

[edit] Special member functions

• default constructor initializes the object with default contents
• copy constructor initializes the object with the contents of another object
• move constructor initializes the object with the contents of other, temporary object, minimizing copying overhead (since C++11)
• assignment operator replaces the contents of the object with the contents of another object
• move assignment operator replaces the contents of the object with the contents of other, temporary object, minimizing copying overhead (since C++11)
• destructor releases claimed resources

[edit] Templates

Allows functions and classes to operate on generic types

• class template declaration
• function template declaration
• template specialization
• parameter packs (since C++11)

[edit] Miscellaneous

• Inline assembly