> Modern C++ should provide a way to efficiently decouple the access model from the memory layout.

I try a lot to make a "array of structs" and also"structure of arrays" for my own little relational language in rust.

Is just not possible (that I know). At best, you could store as packed arrays or arrays of arrays then at runtime static dispatch them.

P.D: Or generate code for both. Anyway is not easy to build... the OPTIMAL algorithms for both cases diverge enough.