Why can't ref struct contain ref field to a ref struct

[petrroll]

^^ question. It'd be very useful in case you need to wrap a (ref) struct with new interface (so that it can be constrained over with generics) that is both ref struct but also contains some non-ref state which means it cannot just be copied into a wrapper without downstream issues.

[333fred]

Doing so is hard; it requires adding more lifetime annotations to the language. See https://github.com/dotnet/csharplang/blob/main/proposals/expand-ref.md#ref-field-to-ref-struct.

[RikkiGibson]

#9152 (reply in thread)