Sorting floating-point values, and NaN

[Vladimir Panteleev]

On Tuesday, 12 November 2013 at 15:56:25 UTC, Andrei Alexandrescu 
wrote:
> I think NaNs are singular unordered values that make invalid 
> inputs for either sort or isSorted. We should simply add an 
> assert to isSorted.

Considering their effect on the program state, NaNs can be seen 
as invalid input, and asserts are not suitable for input 
validation.