Mutably Tagged Types with Size'Class Aspect(gcc.gnu.org)

gcc.gnu.org

Mutably Tagged Types with Size'Class Aspect

https://gcc.gnu.org/onlinedocs/gnat_rm/Mutably-Tagged-Types-with-Size_2019Class-Aspect.html

1 comments

TLDR: You can define a maximum size of any child classes as a property of the parent class, meaning you can have things like arrays of arbitrary child types without having to know all the possible child types in advance and without using pointers.

After some Googling it seems like no other language has implemented a similar feature before, which is surprising with how simple and useful this appears to be for embedded applications.