4.5. Struct Model# TODO 4.5.1. Sequence Sequence 4.5.2. Struct 4.5.2.1. The Struct class 4.5.2.2. Unions 4.5.2.3. Standard Interface 4.5.3. Bitfield 4.5.3.1. Main Interface 4.5.3.2. Default Factory Classes 4.5.3.3. Default Options 4.5.4. Templates TemplateTypeVar istemplate() template() derive()