[swift-evolution] Extend FloatingPoint with tau!

[David Waite]

> On Jun 30, 2016, at 9:22 AM, Stephen Canon via swift-evolution <swift-evolution at swift.org> wrote:
> 
> This was discussed as part of SE-0067.
> 
> The consensus was that pi deserved special treatment, as it is used in general-purpose code an order of magnitude more often than the all other constants combined.  I don’t think that anyone argued against it’s inclusion.

To me, it also makes sense to offer a common transcendental constant with the highest precision available to a particular floating point type.

-DW