std:: is_error_code_enum <std::future_errc>

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std::future_errc
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is_error_code_enum
Defined in header <future>
template <>
struct is_error_code_enum < std:: future_errc > : std:: true_type ;
(since C++11)

Specifies that std::future_errc is an error code enum. This enables std::error_code automatic conversions.

See also

identifies a class as an error_code enumeration
(class template)