* I can see v0.6 was based on generic\_array, but I'm not talking about using typenum-style generics. I'm talking about changing

```
struct Vec<T, const CAP: usize> {
    data: [MaybeUninit<T>; N],
    len: usize
}
```

to

```
struct Vec<T, const CAP: usize, LenT = DefaultLenType<CAP>> {
    data: [MaybeUninit<T>; N],
    len: LenT
}
```