I am using atdgen to create json translators. I am getting “Unbound module Bi_outbuf” errors in the generated code. I can’t find any docs about module Bi_outbuf. Have I failed to install something?

Any reason you need to use atdgen specifically for JSON codecs? Why not use a Yojson PPX like ppx_deriving_yojson or ppx_yojson_conv?

Because I hadn’t heard about them? I will look.

Is there a currently most accepted solution for parsing JSON?

That would probably be yojson: GitHub - ocaml-community/yojson: Low-level JSON parsing and pretty-printing library for OCaml

Just to clarify–are you asking about parsing as in taking a string as input and producing a JSON structure as output? Or decoding as in, taking a JSON structure as input and producing a custom OCaml type as output?

In that case, go with one of the PPXs. They automatically derive encoders/decoders from OCaml type definitions. E.g. say you get a JSON object: {"a": 1, "b": true, "c": "3"} You can declare a corresponding type and automatically derive the codec: type my_type = { a : float; b : bool; c : st…

I recently had the impression adding a ppx had a huge footprint on binary size. (10MB became 20MB with LWT operators so maybe not related to yojson). But watch out in case. (Wanted to have this post appear under the relevant previous posting, so deleted it and re-created but may not :frowning: This…

Maybe if you’re using a lot of them? I just checked and a tool I wrote using ppx_deriving_yojson is 4.1 MB after stripping. It also uses multiple libraries on top of the httpaf stack so it’s doing quite a lot. IMHO this is quite small especially given the usual OCamler attitude of not even blinking …

I did that. I have tried to use that function and keep getting “unbound value”. I have looked for example code and have not found it. I am new to OCaml, but not to programming. With respect to the larger design question, atdgen would be better if it generated more languages, it’s obviously what …

Unbound module Bi_outbuf

Learning

jrootham July 14, 2022, 4:42am 11

I am asking about Decoding.

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Unbound module Bi_outbuf

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