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?

I suspect you’re using yojson 2 (recent!) with atdgen, which might not be up-to-date with that yet. Yojson2 removed biniou as a dependency, which is where Bi_outbuf is from. I think.

So rollback to older Yojson or include biniou as a dependency in dune? Any obvious advantages either way?

Rollback to yojson < 2 should work. Including biniou as a dependency might work, but maybe atdgen expects yojson to use biniou, which it won’t.

A simple dependency didn’t work. Rolling back.

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?

Unbound module Bi_outbuf

Learning

yawaramin July 14, 2022, 12:08am 6

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?

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Unbound module Bi_outbuf

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