RawArray method
Allocates an unslotted pointer-of-pointers from a list of struct arrays.
The caller is responsible for freeing the returned pointer.
Implementation
Pointer<Pointer<T>> RawArray(List<List<X>> arrays) {
final p = Raw(arrays.length);
for (int i = 0; i < arrays.length; i++) p[i] = rawArrayFunc(arrays[i]);
return p;
}