operator==,!=,<,<=> (std::error_condition)
      From cppreference.com
     
     
     
     
      
       <
       
        cpp
       
        |
       
        error
       
        |
       
        error condition
       
      
     
     
     
     | 
           Defined in header
            
            
             <system_error>
            
            | ||
| 
           
            
             bool
            
            operator
            
             ==
            
            
             (
            
            
             const
            
            
             
              std::
              
               error_condition
              
             
            
            
             &
            
            lhs,
             const std:: error_condition & rhs ) noexcept ; | (1) | (since C++11) | 
| 
           
            
             bool
            
            operator
            
             !
            
            
             =
            
            
             (
            
            
             const
            
            
             
              std::
              
               error_condition
              
             
            
            
             &
            
            lhs,
             const std:: error_condition & rhs ) noexcept ; | (2) | (since C++11) (until C++20) | 
| 
           
            
             bool
            
            operator
            
             <
            
            
             (
            
            
             const
            
            
             
              std::
              
               error_condition
              
             
            
            
             &
            
            lhs,
             const std:: error_condition & rhs ) noexcept ; | (3) | (since C++11) (until C++20) | 
| 
           
            
             
              std::
              
               strong_ordering
              
             
            
            operator
            
             <=>
            
            
             (
            
            
             const
            
            
             
              std::
              
               error_condition
              
             
            
            
             &
            
            lhs,
             const std:: error_condition & rhs ) noexcept ; | (4) | (since C++20) | 
| 
           
            
             bool
            
            operator
            
             ==
            
            
             (
            
            
             const
            
            
             
              std::
              
               error_code
              
             
            
            
             &
            
            code,
             const std:: error_condition & cond ) noexcept ; | (5) | (since C++11) | 
| 
           
            
             bool
            
            operator
            
             ==
            
            
             (
            
            
             const
            
            
             
              std::
              
               error_condition
              
             
            
            
             &
            
            cond,
             const std:: error_code & code ) noexcept ; | (5) | (since C++11) (until C++20) | 
| 
           
            
             bool
            
            operator
            
             !
            
            
             =
            
            
             (
            
            
             const
            
            
             
              std::
              
               error_code
              
             
            
            
             &
            
            code,
             const std:: error_condition & cond ) noexcept ; | (6) | (since C++11) (until C++20) | 
| 
           
            
             bool
            
            operator
            
             !
            
            
             =
            
            
             (
            
            
             const
            
            
             
              std::
              
               error_condition
              
             
            
            
             &
            
            cond,
             const std:: error_code & code ) noexcept ; | (6) | (since C++11) (until C++20) | 
Compares two error conditions.
       
        1)
       
       Checks whether
       
        
         lhs
        
       
       and
       
        
         rhs
        
       
       are equal.
      
      
       
        2)
       
       Checks whether
       
        
         lhs
        
       
       and
       
        
         rhs
        
       
       are not equal.
      
      
       
        3)
       
       Checks whether
       
        
         lhs
        
       
       is
       
        less than
       
       
        
         rhs
        
       
       .
      
      
       
        4)
       
       Obtains three-way comparison result of
       
        
         lhs
        
       
       and
       
        
         rhs
        
       
       .
      
      
       
        5)
       
       Checks whether
       
        
         code
        
       
       is a semantic match for
       
        
         cond
        
       
       .
      
      
       
        6)
       
       Checks whether
       
        
         code
        
       
       is not a semantic match for
       
        
         cond
        
       
       .
      
      | 
          The
           | (since C++20) | 
Parameters
| lhs, rhs, cond | - | error conditions to compare | 
| code | - | the error code to compare | 
Return value
       
        1)
       
       
        
         
          true
         
        
       
       if the error category and error value compare equal.
      
      
       
        2)
       
       
        
         
          true
         
        
       
       if the error category or error value compare are not equal.
      
      
       
        3)
       
       
        
         
          true
         
        
       
       if
       
        
         lhs.
         
          category
         
         
          (
         
         
          )
         
         
          <
         
         rhs.
         
          category
         
         
          (
         
         
          )
         
        
       
       . Otherwise,
       
        
         
          true
         
        
       
       if
       
        
         lhs.
         
          category
         
         
          (
         
         
          )
         
         
          ==
         
         rhs.
         
          category
         
         
          (
         
         
          )
         
         
          &&
         
         lhs.
         
          value
         
         
          (
         
         
          )
         
         
          <
         
         rhs.
         
          value
         
         
          (
         
         
          )
         
        
       
       . Otherwise,
       
        
         
          false
         
        
       
       .
      
      
       
        4)
       
       
        
         lhs.
         
          category
         
         
          (
         
         
          )
         
         
          <=>
         
         rhs.
         
          category
         
         
          (
         
         
          )
         
        
       
       if it is not
       
        
         std
         
          ::
         
         
          strong_ordering
         
         
          ::
         
         
          equal
         
        
       
       . Otherwise,
       
        
         lhs.
         
          value
         
         
          (
         
         
          )
         
         
          <=>
         
         rhs.
         
          value
         
         
          (
         
         
          )
         
        
       
       .
      
      
       
        5)
       
       
        
         
          true
         
        
       
       if either
       
        
         code.
         
          category
         
         
          (
         
         
          )
         
         .
         
          equivalent
         
         
          (
         
         code.
         
          value
         
         
          (
         
         
          )
         
         , cond
         
          )
         
        
       
       or
       
        
         cond.
         
          category
         
         
          (
         
         
          )
         
         .
         
          equivalent
         
         
          (
         
         code, cond.
         
          value
         
         
          (
         
         
          )
         
         
          )
         
        
       
       .
      
      
       
        6)
       
       
        
         
          true
         
        
       
       if neither
       
        
         code.
         
          category
         
         
          (
         
         
          )
         
         .
         
          equivalent
         
         
          (
         
         code.
         
          value
         
         
          (
         
         
          )
         
         , cond
         
          )
         
        
       
       nor
       
        
         cond.
         
          category
         
         
          (
         
         
          )
         
         .
         
          equivalent
         
         
          (
         
         code, cond.
         
          value
         
         
          (
         
         
          )
         
         
          )
         
        
       
       .
      
      See also
| 
           
            
             
              [virtual]
             
            
           
           | compares 
          error_code
         and
          error_condition
         for equivalence(virtual public member function of 
           std::error_category
          ) | 
| 
           
            
            
            
             
              (removed in C++20)
             
            
            
             
              (removed in C++20)
             
            
            
             
              (C++20)
             
            
           
           | compares two 
          error_code
         s(function) |