There isn't a state-set function. I'm guessing you meant mrg32k3a-state-set. The state is given and tested as a list, not a vector. It tests the length is 7 because the car is a tag symbol, then it binds the cdr (which has length 6), and then references the 6 indexes into that cdr. Checking for length 7 is correct. Have I misunderstood?
There isn't a state-set function. I'm guessing you meant mrg32k3a-state-set. The state is given and tested as a list, not a vector. It tests the length is 7 because the car is a tag symbol, then it binds the cdr (which has length 6), and then references the 6 indexes into that cdr. Checking for length 7 is correct. Have I misunderstood?