04:45 <sim642> Are there any examples of containerizing an opam package installation in a lightweight manner? That is, the final image shouldn't contain any opam/ocaml stuff (like the repository, compiler, etc) that aren't necessary for executing a binary installed by the package

06:54 <d_bot> <Jektrix> You mean like in Docker?

08:02 <d_bot> <Splingush> The keyword is "multistage docker container". You have one stage where you install your build tools and compile, then a next stage where you only copy the compiled binary over (and copy/install libraries that are dynamically linked). Alpine linux worked for me for the final stage.

08:02 <d_bot> <Splingush> <https://docs.docker.com/develop/develop-images/multistage-build/>

08:04 <d_bot> <Splingush> I checked via ldd to see what libraries are needed for the final container, to be able to run the binary.

08:37 <d_bot> <undu> @companion_cube you're not the only one, it's just that I need to update the compiler first on the product :(

10:46 <d_bot> <Jektrix> I was going to say pretty much exactly what Splingush said 😅

14:43 <d_bot> <Mukal> Hi, I want to write an interpreter with OCaml. I'm still a beginner, still at the semantics and syntax part, so maybe still a long way to go. But would appreciate it if there are readings that I can already access or even better a guide that specific for OCaml which I haven't found. The other guide I found was mainly for other languages, or it does not matter actually? The motivation of writing an interpreter is mainly to understan

14:44 <companion_cube> maybe look at "crafting interpreters"? it uses java in the first half, but OCaml would be suited too

14:53 <d_bot> <Mukal> I've just looked it, looks good. But, what do you mean by "would be suited too"?

14:55 <companion_cube> well, it'd work at least as well as java for the first half

14:56 <d_bot> <Mukal> All right, thank you very much 🙂

15:00 <dmbaturin> The concepts remain the same, mostly. ASTs, environments etc. It's easier to express with algebraic types for sure.

15:04 <d_bot> <Mukal> I see, that's nice then.

16:27 <Yehowshua> I was kind of hoping that `dune utop` would drop me into a seesion where the names in my main are already accessible

16:27 <Yehowshua> but this doesn't seem to be the case?

16:27 <Yehowshua> I have a directory with the two following files:

16:27 <Yehowshua> https://paste.debian.net/1217293/

16:27 <Yehowshua> https://paste.debian.net/1217294/

16:29 <Yehowshua> I should mention I'm a bit new to dune and ocaml in general

16:31 <Yehowshua> Any suggestions on how I might be able to load my main.mlin a repl along with the dependencies of that file?

16:44 <sim642> @Splingush That's what I ended up doing but it feels extremely dirty to have to pick the right things out of the build into the final container. Was hoping dune could do that because it knows all the dependencies and non-dependencies

17:36 <d_bot> <Splingush> sim642: I do not know a better approach than that, but my use-case differs a bit from your apparently as well. I've only ever used it for binaries built myself.

17:36 <d_bot> <Splingush> But I'm confused there for a bit: I thought the dune-stanza-files were specifying on a ocaml-level what dependencies there are, but not on an OS-level. If you built your binary, the used ocaml-libraries for it won't be necessary afterwards, but on an OS-level it will need some dynamically linked libraries at runtime.

17:36 <d_bot> <Splingush> I might be misunderstanding it, my knowledge there is just sufficient to get things going.

17:47 <d_bot> <Splingush> Is your example public? I might not be able to help you further, but providing more concrete information will let others suggest other approaches as well.

18:28 <d_bot> <RegularSpatula> I have an example of a multistage Docker image with a static ocaml binary if you’re interested in a concrete example…it’s a bit messy but it may be useful to see

18:54 <sim642> Here's what I hacked together today (needs cleanup and comments): https://github.com/goblint/analyzer/blob/docker/Dockerfile

18:55 <sim642> One big annoyance in my case is the apron dependency which has C shared libraries. And for some reason --relocatable build still has their RUNPATH as absolute in the binary, so I have to manipulate the binary to make it relative

18:59 <d_bot> <RegularSpatula> Will a static build work in your case?

19:02 <sim642> I haven't tried, but if it's possible then it might even be better for ease of use

19:13 <d_bot> <RegularSpatula> Yeah it was convenient, but my app was pure ocaml so it was no big deal to build it static…not sure with yours how it’ll go with those C reps tho

22:54 <Yehowshua> I want to drop into the ocaml REPL and play around with a few libraries I've installed with Opam, but calling `open somelib` in $ocaml doesn't work directly...

22:55 <Yehowshua> everytime, I have to use topfind and then require...

22:55 <Yehowshua> is this the standard pattern for pulling libs into the REPL

22:55 <Yehowshua> if so, it feels a little kludgy

22:57 <rgrinberg> Yehowshua yes that's how it works. It may seem kludgy if you don't notice the distinction between open and require in this case.

22:57 <rgrinberg> You don't need to open a library's main module to use it

22:57 <Yehowshua> that is also true

22:57 <rgrinberg> it's perfectly fine to refer to it with a qualified name

22:58 <d_bot> <NULL> The `#use "topfind"` is usually automatically run as part if `.ocamlinit`

22:58 <d_bot> <NULL> of*

22:58 <Yehowshua> say I have an ocaml file that uses multiple opam installed libraries... is there any way to load this file into the ocaml repl with all of its dependencies too

23:37 <Yehowshua> Is there a way to have opam uninstall a list of ackages from a file?