Support for field renaming to workaround eg. OCaml keywords. about ppx_yojson HOT 1 CLOSED

Thanks for reporting this and for taking the time to look into the solutions and there pros and cons! Both seem great!

Indeed the prefix thing would be preferable to the attribute solution. It's both easier to use and to implement as the attribute would be attached to the expression bound to the field (nothing impossible to deal with but slightly more tedious).

As you point out there's a risk that it prevents users from writing fields that starts with an underscore. To solve that, what would you think about the following rewriting rule: If the field name starts with an underscore, just remove it unconditionally and leave the rest unchanged.

That way, you should still be able to write JSON field that starts with _ by simply adding an extra leading _, e.g. __secret_field would be rewritten to _secret_field.

The attribute being backward compatible is good indeed but I don't think it would hurt to release a new major version. Actually since we're adding breaking changes, we could also use this occasion to rename the package to ppx_json since it's not yojson specific anymore thanks to your previous contribution!

I think a PR for the rewriting would be welcome as it is bound to get in at some point anyway. I might implement the attribute based solution as well and cut a release with it before to allow for a smooth transition.

from ppx_yojson.