Sorting floating-point values, and NaN

[Vladimir Panteleev]

On Tuesday, 12 November 2013 at 21:03:03 UTC, tn wrote:
>> assert((equiv(a, b) && equiv(b, c)) <= equiv(a, c));
>>
>> ("<=" on Booleans is actually implication.)
>
> Shouldn't the implication be to the other direction? Then it 
> becomes
>
> assert((equiv(a, b) && equiv(b, c)) => equiv(a, c));

<= as in ≤ (less or equal), not ⇐ (reverse implies). <= can be 
used on booleans as "implies" due to the way it treats booleans 
as integers (true as 1, false as 0).