public IEnumerable<IModelDefinition> FilterDoodadSetDefinitions(IList<DoodadSet> sets, IEnumerable<IModelDefinition> doodadDefs) { return !ExtraDoodadSetIndex.HasValue || ExtraDoodadSetIndex >= sets.Count ? DefinitionsForSet(doodadDefs, sets[0]) : DefinitionsForSet(doodadDefs, sets[ExtraDoodadSetIndex.Value]); }