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From: Tim Rentsch <tr.17687@z991.linuxsc.com>
Newsgroups: comp.lang.c
Subject: Re: Hex string literals (was Re: C23 thoughts and opinions)
Date: Tue, 18 Jun 2024 11:12:21 -0700
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bart <bc@freeuk.com> writes:

> [...] I noticed this strange discrepancy between
> between my hex floats and C's.  In C, this value:
>
>     0x12.34p10
>
> has the decimal value 18640.0; why was that?  It turns that this is:
>
>    18.203125 x 2 ** 10
>
> The main part is interpreted as actual hex;  the exponent is in
> decimal, and exponent scaling is in binary bits.  So THREE diferent
> bases are involved!
>
> In my scheme (which as I said worked for bases from 2 to 16), the
> 0x12.34p10 value would mean this:
>
>    18.203125 x 16 ** 16        ~= 3.58e20
>
> The same base is used for all parts, including the exponent, and the
> digits that are to be shifted.  After all in decimal, 12.34e10 would
> mean:
>
>    12.34 x 10 ** 10            = 123400000000.0
>
> In my language, a base 5 version 5x12.34e10  (not valid below base 5)
> would mean this (I think, as I no longer have the compiler):
>
>    7.76 x 5 ** 5               = 24250.0
>
> This has a consistency lacking in C's hex floats.

The C hex float format has benefits that your format does not.