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Re: [Cbor] 7049bis: Diagnostic notation gaps

Thiago Macieira <thiago.macieira@intel.com> Fri, 11 September 2020 21:47 UTC

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From: Thiago Macieira <thiago.macieira@intel.com>
To: cbor@ietf.org
Date: Fri, 11 Sep 2020 14:47:14 -0700
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Subject: Re: [Cbor] 7049bis: Diagnostic notation gaps
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On Friday, 11 September 2020 14:30:24 PDT Thiago Macieira wrote:
> It would be far easier to dump the binary representation of the entire
> floating point number, including the exponent bits. If this format were
> allowed, a diagnostic printer with no support for stringifying floating
> point numbers could use it for other values too.

By the way, should we explicitly allow hexadecimal floating point notation?

Appendix A has:

   | 3.4028234663852886e+38       | 0xfa7f7fffff                       |

This would also allow printing 0xf.fffffp+124 or 0x1.fffffep+127. The first 
form is what glibc's printf %a formatter prints, the second is the far easier 
one to produce without a floating-point formatter, by just decoding 0x7f7fffff 
as sign = 0, unbiased exp = 127 , significand = 0xffffff.
-- 
Thiago Macieira - thiago.macieira (AT) intel.com
  Software Architect - Intel DPG Cloud Engineering

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