C++ keyword:`class`

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class
compl
concept (C++20)
const
consteval (C++20)
constexpr (C++11)
constinit (C++20)
const_cast
continue
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decltype (C++11)
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true
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typeid
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unsigned
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volatile
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xor
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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)

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[edit]Usage

declaration of a class

declaration of a scoped enumeration type

(since C++11)

In atemplate declaration,class can be used to introducetype template parameters andtemplate 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 anelaborated type specifier.

[edit]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}