[swift-evolution] SetAlgebra naming update

[Thorsten Seitz]

> Am 30.03.2016 um 16:49 schrieb Dave Abrahams <dabrahams at apple.com>:
> 
>> on Wed Mar 30 2016, Thorsten Seitz <tseitz42-AT-icloud.com> wrote:
>> 
>> That's certainly an improvement, but why "formIntersection" instead of
>> "intersect" (in analogy to "subtract")?
> 
> 1. Consistency with union, which is more closely related than subtract.

I'd prefer consistency with the verb rule here (using formXXX only as last resort).


> 2. "Intersect" actually has the wrong meaning as an imperative.  If you
>   tell set A to intersect set B, and then ask whether A intersects B
>   (!A.isDisjoint(with: B)), you would expect an answer of true.

Sorry, but I do not agree. With that reasoning I would have to expect a.intersection(b) to be not empty. 

-Thorsten