SysML2.0: Links to specification, Annex, and SysMLv2 GitHub PILOT code examples that directly use an ISQ «attribute def» as attribute type (an opposed to subsetting the ISQ «attribute» equivalent).

There is also a full discussion of this in the Webel SysMLv2 course: The gist is that since coverage of specific kinds of quantities in «attribute» form is not complete anyway, one might as well just use an «attribute def» as type. The SysMLv2 samples, Annex, and SysMLv2 PILOT GitHub examples use both forms.