Jakub Kicinski [off-list ref] writes:

On Sun, 19 Mar 2023 19:38:01 +0000 Donald Hunter wrote:

quoted

                 enum: [ unused, pad, flag, binary, u8, u16, u32, u64, s32, s64,
-                        string, nest, array-nest, nest-type-value ]
+                        string, nest, array-nest, nest-type-value, struct ]

I wonder if we should also only allow struct as a subtype of binary?

Structs can technically grow with newer kernels (i.e. new members can
be added at the end). So I think for languages like C we will still
need to expose to the user the original length of the attribute.
And binary comes with a length so codgen reuse fits nicely.

Either way - docs need to be updated.

Yep, as I was replying to your previous comment, I started to think
about making struct a subtype of binary. That would make a struct attr
something like:

 -
   name: stats
   type: binary
   sub-type: struct
   struct: vport-stats

I originally chose 'struct' as the attr name, following the pattern that
'enum' is used for enum names but I'm not sure it's clear enough. Maybe
'sub-type-name' would be better?

I will update the documentation for this.