Re: [Json] JSON Schema Language: extensibility and unspecified properties

[Pete Cordell <[e-mail]>]

On 20/08/2019 04:26, Ulysse Carion wrote:
>> An "int53" type or other means of requiring that a JSON number have zero fractional part and magnitude no greater than 2^53.
> 
> Ah -- in that case, I think it fails the other part of the criterion I
> put forward: having "a clear mapping to programming languages in
> widespread use today." In case the language is unclear, my thinking
> was that both (1) and (2) need to be satisfied for something to be
> included in the spec.
> 
> At least on my view, int53's correspondence is unclear -- should it be
> a double/f64, or a long/int64_t, with a runtime check to make sure
> it's in-bounds? That's not very idiomatic. Better, in my view, to
> stick to uncontroversial things?

IMO, the schema should be about representing what the protocol needs 
rather than how it is represented on a target machine.

An implementation may choose to store an int8 in a 32-bit integer. As 
long as it does suitable bounds checking at the appropriate points 
nothing outside the machine need know that it has chosen to do that.

There may be cases where there is a need for something that is larger 
than int32 but more inter-operable than int64. int53 satisfies that need 
in many cases.

Mapping it to either double/f64 or long/int64_t is a local 
implementation choice.

Pete.
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Pete Cordell
Codalogic Ltd
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