Write double to text file, then read it back later without losing precision

[Andrew Brown via Digitalmars-d-learn]

I'm sure it will be, thank you very much.

On Monday, 19 May 2014 at 15:57:53 UTC, bearophile wrote:
> Andrew Brown:
>
>> I would like to write a double to a text file as hexadecimal 
>> and then read it back in without losing information.
>
> Is this good enough for you?
>
> void main() {
>     import std.stdio, std.math;
>
>     auto fout = File("ouput.txt", "w");
>     fout.writef("%a", PI);
>     fout.close;
>
>     auto fin = File("ouput.txt");
>     real r;
>     fin.readf("%f", &r);
>     fin.close;
>     assert(PI == r);
> }
>
> Bye,
> bearophile