> On May 12, 2023, at 8:59 AM, Alexander Grund via Boost <boost(a)lists.boost.org> wrote:
>
> Am 12.05.23 um 02:52 schrieb Gavin Lambert via Boost:
>> Mere moments ago, quoth I:
>>>> Hex format will be of the form +1.0e2p+5. The integer part will
>>>> always be 0 or 1. The exponent will be with a p instead of an e like
>>>> in base 10 formats.
>> (Also, FWIW, gcc fails to parse that with the leading +. And I
>> couldn't even find any online calculators that understand this format.)
> According to cppreference the floating point parser should not support it:
>
> "the plus sign is not recognized outside of the exponent (only the
> minus sign is permitted at the beginning)"
>
> So I'd say that is a bug in Boost charconv given that it wants to be
> as-if the standard one.
>
You two are correct that a value with a leading plus sign should be EINVAL rather than ignoring it during parsing. I opened an issue, and will address it.
Matt
