cpp/error/error condition/operator cmp

Compares two error conditions.

@1@ Checks whether and  are equal. @2@ Checks whether and  are not equal. @3@ Checks whether is less than. @4@ Obtains three-way comparison result of and. @5@ Checks whether is a semantic match for. @6@ Checks whether is not a semantic match for.

Return value
@1@ if the error category and error value compare equal. @2@ if the error category or error value compare are not equal. @3@ if. Otherwise, if. Otherwise,. @4@ if it is not. Otherwise,. @5@ if either  or. @6@ if neither  nor.