copy

fun ~~copy~~(text: TextElem = this.text, image: ImageElem = this.image, video: VideoElem = this.video, url: URLElem = this.url, type: Int = this.elemType.value): Elem(source)

此类型不再作为 data class 进行公开，请尽量避免使用 data class 默认生成的相关语法/特性。