Peter Eisentraut <peter.eisentr...@2ndquadrant.com> writes: > These two items are now outstanding: > > On 4/10/18 07:33, Dagfinn Ilmari Mannsåker wrote: >> 2) jsonb scalar values are passed to the plperl function wrapped in not >> one, but _two_ layers of references > > I don't understand this one, or why it's a problem, or what to do about it.
It means that if you call a jsonb-transforming pl/perl function like select somefunc(jsonb '42'); it receives not the scalar 42, but reference to a reference to the scalar (**int instead of an int, in C terms). This is not caught by the current round-trip tests because the output transform automatically dereferences any number of references on the way out again. The fix is to reshuffle the newRV() calls in Jsonb_to_SV() and jsonb_to_plperl(). I am working on a patch (and improved tests) for this, but have not have had time to finish it yet. I hope be able to in the next week or so. >> 3) jsonb numeric values are passed as perl's NV (floating point) type, >> losing precision if they're integers that would fit in an IV or UV. > > This seems fixable, but perhaps we need to think through whether this > will result in other strange behaviors. Nubers > 2⁵³ are not "interoperable" in the sense of the JSON spec, because JavaScript only has doubles, but it seems desirable to preserve whatever precision one reasonably can, and I can't think of any downsides. We already support the full numeric range when processing JSONB in SQL, it's just in the PL/Perl transform (and possibly PL/Python, I didn't look) we're losing precision. Perl can also be configured to use long double or __float128 (via libquadmath) for its NV type, but I think preserving 64bit integers when building against a Perl with a 64bit integer type would be sufficient. - ilmari -- "The surreality of the universe tends towards a maximum" -- Skud's Law "Never formulate a law or axiom that you're not prepared to live with the consequences of." -- Skud's Meta-Law