Replacement for snprintf

[Stefan Koch]

On Thursday, 31 October 2019 at 20:20:24 UTC, Walter Bright wrote:
> On 10/31/2019 1:27 AM, drug wrote:
>> In some cases it is much more productive to have text 
>> representation of data than binary ones. Initially I believed 
>> too that binary representation is the more suitable but 
>> afterwards I  was forced to use text format and that gives me 
>> a good result.
>
> To get round-trip 100% accuracy, print the floats in hex using 
> the %A format.

DtoA is also supposed to have 100% accuracy, when it comes to 
value, not necessarily to binary representation though.

I'd still prefer grisu2 over ryu, since it easier to understand 
and I already have a ctfeable version of it. (it can't be safe 
though since it casts double* to ulong*)