// +build go1.13 package errors import ( baseErrors "errors" ) // find error in any wrapped error func As(err error, target interface{}) bool { return baseErrors.As(err, target) } // Is detects whether the error is equal to a given error. Errors // are considered equal by this function if they are matched by errors.Is // or if their contained errors are matched through errors.Is func Is(e error, original error) bool { if baseErrors.Is(e, original) { return true } if e, ok := e.(*Error); ok { return Is(e.Err, original) } if original, ok := original.(*Error); ok { return Is(e, original.Err) } return false }