protected TemplateGroup GetTemplateGroup(List<string> templateNames) { if (tg == null) { // combile the header and all .st files and load everything into a TemplateGroup tg = new TemplateGroup(); foreach (var templateName in templateNames) { tg.ImportTemplates(GetTemplateGroupFromResource(templateName)); } foreach (var type in attributeRenderers.Keys) { var renderer = attributeRenderers[type]; tg.RegisterRenderer(type, renderer); } } return tg; }