C++ keywords: class

 

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C++ language

General topics
Preprocessor Comments	Keywords Escape sequences
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if	switch
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for range-for (C++11)	while do-while
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decltype (C++11) auto (C++11) alignas (C++11)	const/volatile constexpr (C++11)
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static_cast - dynamic_cast
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Class declaration Constructors this pointer	Access specifiers friend specifier
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Virtual function override specifier (C++11) final specifier (C++11)	explicit (C++11) static
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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)
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Inline assembly	History of C++

 

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 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) override (C++11)	import (C++20) module (C++20)

 

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 argument
void qux() {
    T t;
}
 
enum class Pub { // scoped enum, since C++11
    b, d, p, q
};
 
int main()
{
    Bar Bar(1);
    class Bar Bar2(2); // elaborated type
}