I'm reading a SystemC lecture which describes use of operator overloading of comma in their syntax to support concatenation. So, for example, they support the data operations below sc_uint<4> a, b, d, e; sc_unit<8> c; c = (a, b); (d, e) = c; As I understand it, SystemC is C++. I didn't find commas among the overloadable D operators. Is that correct?