labeled tuples ?

[chetmurthy]

Have you thought about how to support labeled tuples ?

So for the type (int * bool), the value (5, false) gets serialized as [5, false].
So maybe for the type (a:int * b:bool) the value (~a:5, ~b:true) might get serialized as [["a",5], ["b",false]] ?

I'm implementing this support for pa_ppx.deriving_plugins.yojson, so I have to make a decision about how to do it, so if you already had a decision made, I'd be happy to follow along.

[NathanReb]

Serializing labeled tuples as JSON objects sound sane to me! I'll try and submit a PR here with the support soon!

[chetmurthy]

Nathan, I also posted at the OCaml discuss forum, and .... well, I have to say I was convinced by that discussion that the best thing is to just erase the labels and keep going.

https://discuss.ocaml.org/t/labled-tuples-for-derived-yojson-serializers/18061

Whatever your decision is, if you could post about it with maybe one or two examples, I would appreciate it -- if you decide to go with some other design, I would of course follow your lead. If you -do- decide to go with a dictionary, I wonder if there's some way you could use an attribute on the type to indicate conversion to an unlabeled arrays (so that both wire-formats were allowed)? B/c I have to say, the discussion firmly convinced me that the unlabeled array is superior.

OK, I have to confess that it doesn't hurt, that it's also soooo much easier to implement, haha!

[NathanReb]

Thanks for the pointer, I just had a look and I agree that ignoring the labels probably is the right thing to do here indeed. At a glance it seemed like a good idea but the fact that the labeling is per-element makes it not worth the pain, better to treat all tuples equally, users can define records if they want JSON objects.

That will still require a patch though as labeled tuples are encoded in ppxlib's AST, see https://ocaml-ppx.github.io/ppxlib/ppxlib/compatibility.html#future_compilers.