C++ keywords: extern

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C++ Standard Library
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C++ keywords
and and_eq alignas alignof asm auto bitand bitor bool break case catch char char16_t char32_t class compl const constexpr const_cast continue decltype default delete double dynamic_cast else enum explicit export extern false float for friend goto if inline int long mutable namespace new noexcept not not_eq nullptr operator or or_eq private protected public register reinterpret_cast return short signed sizeof static static_assert static_cast struct switch template this thread_local throw true try typedef typeid typename union unsigned using virtual void volatile wchar_t while xor xor_eq

[edit] Usage

• static storage duration with external linkage specifier