Webel: SysML4Mathematica: An Association used as the Type of an argument or return is represented by a Block '<||>'. A List used as as the Type of an argument or return is represented by a Block '{}'.
Webel: SysML4Mathematica: An '@' prefix in the name of a Block indicates a Mathematica data structure (such as an Association or List) that is not represented by an MTools class in the Mathematica code