/// <summary>
/// Creates and seeds a new part.
/// </summary>
/// <param name="item">The item this part should belong to.</param>
/// <param name="roleId">The optional part role ID.</param>
/// <param name="factory">The part seeder factory. This is used
/// for layer parts, which need to seed a set of fragments.</param>
/// <returns>A new part.</returns>
public abstract IPart GetPart(IItem item, string roleId,
PartSeederFactory factory);
/// <summary>
/// Initializes a new instance of the <see cref="CadmusSeeder"/> class.
/// </summary>
/// <param name="factory">The part seeder factory.</param>
/// <exception cref="ArgumentNullException">factory</exception>
public CadmusSeeder(PartSeederFactory factory)
{
_factory = factory
?? throw new ArgumentNullException(nameof(factory));
_options = _factory.GetSeedOptions();
}