- Both sides pass messages to each other. Both of them talk through C ABI. My model was synchronous though. Async is certainly better.
- I used the protobuf binary protocol for message passing. Faster and probably more efficient than, say, JSON. But both sides may have copies of the same data for this reason.
I've written down my approach, which roughly aligns with yours, in the project's README.
What I wanted to do was for OCaml side to allocate data in memory, and for Swift to access the same memory through some commonly agreed upon protocol (protobuf itself maybe?). But I haven't yet explored how difficult this could be with GC coming in play. I think OCaml does have a few tricks to tell GC to not collect objects being shared through C ABI (https://ocaml.org/manual/5.3/intfc.html#s:c-gc-harmony), but I haven't looked into this enough to be sure.
Your projects will sure help me figure out the concepts!
Nice! Yeah, using protobufs seems reasonable. Re. GC, Racket has support for "freezing" values in place to prevent the GC from moving them, but freezing too many values can impact the GC's operation so I'd watch out for that if that's possible in OCaml.
In my PoC (https://github.com/jbhoot/poc-ocaml-logic-native-ui) - a tiny hello world CLI on macOS, that has a Swift "frontend" and OCaml "backend" - I followed a similar model:
- Both sides pass messages to each other. Both of them talk through C ABI. My model was synchronous though. Async is certainly better. - I used the protobuf binary protocol for message passing. Faster and probably more efficient than, say, JSON. But both sides may have copies of the same data for this reason.
I've written down my approach, which roughly aligns with yours, in the project's README.
What I wanted to do was for OCaml side to allocate data in memory, and for Swift to access the same memory through some commonly agreed upon protocol (protobuf itself maybe?). But I haven't yet explored how difficult this could be with GC coming in play. I think OCaml does have a few tricks to tell GC to not collect objects being shared through C ABI (https://ocaml.org/manual/5.3/intfc.html#s:c-gc-harmony), but I haven't looked into this enough to be sure.
Your projects will sure help me figure out the concepts!