Which, in practice, is a terrible oversight. I've honestly never seen a JSON store/transport/serde in practice without dates and/or times in them. There's always some updated_at or captured_on somewhere in the API or dataset.
Of all the data-types needed, I'd say dates are amongst the most important. At least more important in practice than floats; which JSON does support for odd reasons. Especially with dates being ambigous at best and inconsistent at worst.
Pubquiz: when was/or will be, how much paid? { currency: "THB", paid_at: "04-03-2566", amount: 13.37 }¹ - JSON is neat for simple use-cases, but utterly impractical for when precision and correctness is required. Yet here we are, building around and on top of it, to get that correctness and precision.
¹I'm messing a bit, 'cause this calendar isn't used in practice for such use-cases anymore. Hardly. But I've seen this with Hijri calendars. And those silly US date-formats. I've seen it "solved" with complex structs like { created_at: { year: 2022, day: ... , timezone:xxx}". I've myself "fixed" floating-point precision issues in financial applications that used JSON by using all-strings: "{ currency: "USD", amount_in_cents: "1337" } and such.
There's standard to encode dates to string. It's called ISO-8601 and it's supported everywhere.
Also JSON poses no particular limits which would force anyone to encode string as number.
No. I'm complaining that JSON is too limited. And that it's "type system" is lacking so much that I have to resort to hacks like encoding numbers in strings. Which I think is embarrassing for an industry.
> There's standard to encode dates to string. It's called ISO-8601 and it's supported everywhere.
It's not. Too many servers and services use formats other than ISO-8601. Should I call Visa that their export formats suck? Or that Random API that their JSON datefields should be changed to ISO-8601. It's supported in most languages. But e.g. something widely used as Google Sheets doesn't support this: If you get a JSON or CSV with ISO-8601 into Google sheets, a lot of string parsing and even regexes are needed to turn it into a proper date.
Saying "we use ISO-8601 and that solved everything" only works if you never need any service outside of yours and never interop or exchange data with other services. Which in practice is never for anything remotely successful.
I have yet to see Time be easy. Anywhere. At all. From daylight savings being state-dependent, system times resetting to rand, right down to CPU monotonic timing.
Using Time handling as a criticism to JSON's architecture doesn't hold water.
JSON on the other hand does not separate types and data, the types are implicitly contained in the data. So you can get type information from the data without a schema, at least up to the point where JSON's simple type system is no longer expressive enough, then you need - just as with XML - a schema to get the correct type information, for example to distinguish actual strings and dates.
If you really need this, nobody stops you from including type information in XMLs, have a type attribute on elements or <quote>"strings"</quote> as compared to <numbers>123</numbers> and use that. You will of course have to do this on your own, that is just not the way XML is supposed to be used.