2 select cvt_a->attributes.count(\nan_b2f) || cvt_a->attributes.count(\nan_f2b)
6 select cvt_b->attributes.count(\nan_b2f) || cvt_b->attributes.count(\nan_f2b)
7 index <IdString> cvt_b->type === cvt_a->type
8 index <SigSpec> port(cvt_b, \A) === port(cvt_a, \A)