Before instance variables were used to store the actual data
While this worked it was a double mental loop and (more importantly) did not allow the same memory access
Ie, in the interpreter the types for args had to be set correctly
But they don't need to be until we walk the list, when we can get the types from the method.
In short, now the fake memory may be used as memory, by indexing into it
We now have to use attr reader/writers that map to the fake memory
And while this is possible, it means a lot more self. than i would like
Also the compiler whill have to undo those attr to instance acess at some point
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