package errhttp type InsufficientStorage interface { ServerError InsufficientStorage() } var _ InsufficientStorage = internalInsufficientStorage{} type internalInsufficientStorage struct { err error } func InsufficientStorageWrap(err error) error { return internalInsufficientStorage{ err:err, } } func (receiver internalInsufficientStorage) Error() string { return receiver.err.Error() } func (receiver internalInsufficientStorage) Err() error { return receiver.err } func (internalInsufficientStorage) ServerError() { // Nothing here. } func (internalInsufficientStorage) InsufficientStorage() { // Nothing here. } func (receiver internalInsufficientStorage) Unwrap() error { return receiver.err }