Implement missing JSON operators

[ycanardeau]

This PR implements the <@, ?, ?| and ?& JSON operators. Some of the test cases were taken from https://www.postgresql.org/docs/15/functions-json.html.

[oguimbal]

Hi ! Thanks for the PR.

I believe you have missed use cases ... for instance when json arguments are numbers, or null.

i.e. not the postgres NULL (in which case the function will not be called, because it does not state that it supports null arguments), but the json 'null'::jsonb kind of null (which is different, and will effectively pass a null argument to the function).

FYI, here is the ? implementation as I am using it in one of my projects:

  implementation: (a, b) => Array.isArray(a) ? a.includes(b) : typeof a === 'object' && b && a && b in a;

Not sure if it is exactly accurate, but I believe it behaves as expected when a is null 😊