05:26 <twobitsprite> What's the advantage of using modules over objects? I mean, I feel like `obj#meth a b` is cleaner than `Mod.func obj a b`

06:50 <discocaml> <ada2k> twobitsprite: a module can contain multiple types and group functions logically, since ocaml (thankfully) does not have static/class methods you have to initialise an object to call any method on it, and modules are generally lighter in both performance and complexity

06:53 <discocaml> <ada2k> by complexity

06:55 <discocaml> <ada2k> e.g. access to a record's field is just controlled by it being a non-opaque type, whereas objects need explicit getters and setters to lift values out of the object

09:22 <discocaml> <dinosaure> Also, objects are not on top of the priority for the OCaml core team. It's not widely used and OCaml's objects are different than Java's objects (which increases the difficulty to learn and use them).

11:02 <discocaml> <ada2k> basically, you'll know when you need them. they're a nice tool in ocaml

11:03 <discocaml> <ada2k> *niche

19:40 <twobitsprite> ada2k: ewww, I hate getters and setters. I've never understood the point of "opaque" objects, I'm used to python's OO style. Anyways, thanks for explaining the difference to me

19:41 <twobitsprite> modules it is, from now on XD

21:59 <discocaml> <barconstruction> I think getters and setters are often poorly motivated. I didn't understand them when I was learning Java on high school. I don't remember the teacher giving any examples of invariants that we wanted to maintain for objects which would have illustrated why you want to control access to the field.

22:43 <discocaml> <ada2k> twobitsprite: objects are super useful when you actually do need concurrency or multiple implementations for a type

22:44 <discocaml> <ada2k> but first class modules are a powerful enough tool that objects only get used when those two things are a real benefit

22:45 <discocaml> <ada2k> think some of the JS converters use objects to represent javascript types, many i/o libraries use them too. it’s a targeted tool

23:17 <discocaml> <deepspacejohn> in OCaml objects are structurally typed values whereas modules contain (mostly nominal) types and values. In practice there's a difference between using an object with an `add` method and a value of `Queue.t` type that you can use `Queue.add` on.

23:39 <discocaml> <deepspacejohn> Question: is there a limit to the number of constructors an extensible variant can have, and would calling a function like this enough times reach the limit? `let f () = let module M = struct type exn += E end in raise M.E`