C++ keyword:class

 

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C++ language

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Class template Function template	Template specialization Parameter packs(C++11)
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Keywords

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
final (C++11) import (C++20) module (C++20)	override (C++11) post (C++26) pre (C++26)	replaceable_if_eligible (C++26) trivially_relocatable_if_eligible (C++26)

 

Usage

• declaration of a class

declaration of a scoped enumeration type

(since C++11)

• In a template declaration, class can be used to introduce type template parameters and template template parameters
• If a function or a variable exists in scope with the name identical to the name of a class type, class can be prepended to the name for disambiguation, resulting in an elaborated type specifier.

Example

Run this code

class Foo;// forward declaration of a class   class Bar // definition of a class{public: Bar(int i): m_i(i){}private:int m_i;};   template<class T>// template argumentvoid qux(){ T t;}   enumclass Pub // scoped enum, since C++11{ b, d, p, q };   int main(){ Bar Bar(1);// variable Bar hides type Bar Bar Bar2(2);// compiler errorclass Bar Bar3(3);// elaborated type}

See also

• struct, union

final

(since C++11)

• enum
• typename
• template

concept, requires

(since C++20)