Comment by MathMonkeyMan

> > you don’t need to write destructors

>> I think this is not accurate. Destructors are not

> deallocators, they are supposed to set the object field in

> an invalid state. Now truth is that both are often called

> together, e.g `delete`.

If the object manages some resource other than memory, and if the object's lifetime is intended to guard the resource, then a destructor is needed.

But if the object manages memory only, as is often the case, and all of that memory came from the arena, then you really don't need to call any destructors.

This is the approach taken in one C++ [library][1] I've worked with, where objects represented scalar values to be used en masse for spreadsheet-like applications. In those applications (especially in 32-bit mode), being able to omit an allocator pointer and neglect a destructor call made things smaller and faster.

[1]: https://bloomberg.github.io/bde-resources/doxygen/bde_api_pr...