std::is_error_code_enum
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                    < cpp | error | error code
                    
                                                            
                    | Defined in header  <system_error> | ||
| template< class T > struct is_error_code_enum; | (since C++11) | |
If T is an error code enumeration, this template provides the member constant value equal true.  For any other type, value is false.
This template may be specialized for a user-defined type to indicate that the type is eligible for std::error_code and std::error_condition automatic conversions.
The following classes of the standard library are an error code enum:
| Contents | 
[edit] Helper variable template
| template< class T > inline constexpr bool is_error_code_enum_v = is_error_code_enum<T>::value; | (since C++17) | |
Inherited from std::integral_constant
Member constants
| value [static] | true if Tis an error code enum, false otherwise(public static member constant) | 
Member functions
| operator bool | converts the object to bool, returns value(public member function) | 
| operator() (C++14) | returns value(public member function) | 
Member types
| Type | Definition | 
| value_type | bool | 
| type | std::integral_constant<bool, value> | 
[edit] See also
| (C++11) | identifies an enumeration as an std::error_condition (class template) | 


