Re: [Json] [Cbor] JSON and int64s - any change in current best practice since I-JSON

[Jeremy O'Donoghue <[e-mail]>]

Yes.

I think the document should provide text something like the following:

“Note: Implementors are advised that the built-in numeric parsers in some programming implementations accept only a subset of the floating point syntax defined in [IEEE 754] and used in this document. In particular, care may be required with respect to supporting input with leading and/or trailing zeros.”

Might also be good to have a couple of examples which are known to fail with at least some language parsers. At least for myself, the first thing I do in an implementation is to implement all of the examples in an RFC as test cases, so this is an easy way to ensure that implementers catch any issues.

Best regards
Jeremy

On 27/01/2024, 16:45, "CBOR" <[e-mail]> wrote:

WARNING: This email originated from outside of Qualcomm. Please be wary of any links or attachments, and do not enable macros.

On 2024-01-27, at 17:06, Jeremy O'Donoghue <[e-mail]> wrote:
>
> As a minimum there needs to be guidance about the use of in-built language numeric parsers and formatting in the text.

If it helps, this is what I did in Ruby (which allows all-zeros elision neither in the integer part nor in the fractional part) [1], slightly edited:

    if /p/i =~ text_value
      Float(text_value.sub(/x\./i, "x0.").sub(/\.p/i, ".0p”))
    else
      Integer(text_value)
    end

This uses case-insensitive matches (/p/i) for the presence of the character p or P (which distinguishes a hex float from a hex integer), for a dot right after the x or X, or a dot right before the p or P.

The equivalent for decimal floats is similar, but more intricately installed in the ABNF, please see [1].

Do you think this approach needs to be hinted at in the document?

Grüße, Carsten

[1]: https://github.com/cabo/edn-abnf/commit/8a5f56#diff-b8a7b57
_______________________________________________
CBOR mailing list
[e-mail]
https://www.ietf.org/mailman/listinfo/cbor