std::is_error_condition_enum
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                    < cpp | error | error condition
                    
                                                            
                    |   Defined in header  
<system_error>
  | 
||
|   template< class T > 
struct is_error_condition_enum;  | 
(since C++11) | |
If T is an error condition enum, 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 class of the standard library is an error condition enum: std::errc.
Contents | 
[edit] Helper variable template
|   template< class T > 
constexpr bool is_error_condition_enum_v = is_error_condition_enum<T>::value;  | 
(since C++17) | |
Inherited from std::integral_constant
Member constants
|    value 
[static] 
 | 
   true if  T is an error condition 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 a class as an error_code enumeration  (class template)  | 
|    (library fundamentals TS) 
 | 
   variable template alias of std::is_error_condition_enum::value  (variable template)  |