Aggregate vs. Any, for scanning objects such as IEnumerable<bool>

Question

Just wondered if any LINQ guru might be able to shed light on how Aggregate and Any work under the hood.

Imagine that I have an IEnumerable which stores the results of testing an array for a given condition. I want to determine whether any element of the array is false. Is there any reason I should prefer one option above the other?

IEnumerable<bool> results = PerformTests();

return results.Any(r => !r); //Option 1
return results.Aggregate((h, t) => h && t); //Option 2

In production code I'd tend towards 1 as it's more obvious but out of curiosity wondered whether there's a difference in the way these are evalulated under the hood.

Answer 1

Yes, definitely prefer option 1 - it will stop as soon as it finds any value which is false.

Option 2 will go through the whole array.

Then there's the readability issue as well, of course :)

Answer 2

Jon beat me again, but to add some more text:

Aggregate always needs to consume the whole IEnumerable<T>, because that's exactly what it's supposed to do: To generate a dataset from your (complete) source. It's the "Reduce" in the well-known Map/Reduce scenario.