code: func (m *modelPrinter) VisitPrimitive(p *proto.Primitive) {
  	if err := m.PrintKindAndVersion(); err != nil {
  		m.Error = err
  		return
  	}
  
  	if m.Type == "" {
  		m.Type = GetTypeName(p)
  	}
  	if err := m.Writer.Write("FIELD:    %s <%s>\n", m.Name, m.Type); err != nil {
  		m.Error = err
  		return
  	}
  	m.Error = m.PrintDescription(p)
  }
docs: // VisitPrimitive prints a field type and its description.