9999999999999999.0 - 9999999999999998.0

[Samir]

On Sunday, 6 January 2019 at 01:05:08 UTC, Adam D. Ruppe wrote:
> That's because it is done at compile time, since both are 
> compile-time constants. The compiler will evaluate it using the 
> maximum precision available to the compiler, ignoring your 
> request to cast it to double (which annoys some people who 
> value predictability over precision btw). At different 
> precisions, you get different results.

Thanks for that explanation, Adam!  Very helpful.

On Sunday, 6 January 2019 at 03:33:45 UTC, Jesse Phillips wrote:
> Since you got your answer you may also like
> http://dconf.org/2016/talks/clugston.html

Thank you for pointing out that talk, Jesse.  I will set aside 
some time to go through that!

Samir