If you keep the interface the exact same, you run into some pretty big complications, as with the current interface you can change one row out with another obje

If you keep the interface the exact same, you run into some pretty big complications, as with the current interface you can change one row out with another object with a single statement, or similarly get a row object as such (which you do implicitly in "arr[a][b]"!). So you'd have to still store an object per row in addition to the data to keep their identity the same each time they're gotten, and have some way to transform out of this representation if the last reference to the 2D array is via a single row of it, GCing away the rest of the rows.