Question

Given a finite list of elements, how can I create a (lazily-evaluated, thanks LINQ!) infinite list that just keeps iterating over my initial list?

If the initial list is {1, 2, 3}, I want the new list to return {1, 2, 3, 1, 2, 3, 1, ...}

Answer 1

yield return is a fairly handy operator for this, although it doesn’t really require LINQ specifically.

IEnumerable<int> GetInfiniteSeries(IEnumerable<int> items) {
    while (true) {
       foreach (var item in items) { 
           yield return item;
       }
    }
}