What is "FilterResult" type?

[Bahman Movaqar via Digitalmars-d-learn]

On Wednesday, 9 September 2015 at 13:16:49 UTC, cym13 wrote:
>> True.  But is pumping the output of `filter` as the seed into 
>> `reduce` really considered weird usage!?
>
> I don't think it is really weird per se, I just can't think of 
> a case where there isn't a better way to do it. I find it 
> completely unreadable frankly, and I generally avoid reduce 
> when I can because it is not UFCS-able. This is only personal 
> opinion though.

Now I see your point.  I too find fold/reduce the least 
transparent verb of the list comprehension.  And certainly your 
point about UFCS adds to it.