public ChapterId([NotNull] VolumeId volume, int chapterNumber) { Volume = volume ?? throw new ArgumentNullException(nameof(volume)); ChapterNumber = chapterNumber; }
public IEnumerable <ChapterId> EnumerateChapters([NotNull] VolumeId volume) { return(Enumerate(volume.VolumeNumber, 0, "chapter") .Select(x => new ChapterId(volume, x))); }