How do you work with IList<> in F#?

Question

I have a list of type IList<Effort>. The model Effort contains a float called Amount. I would like to return the sum of Amount for the whole list, in F#. How would this be achieved?

Answer 1

efforts |> Seq.sumBy (fun e -> e.Amount)

Answer 2

Upvoted the answers of Seq.fold, pipelined Seq.fold, and pipelined Seq.sumBy (I like the third one best).

That said, no one has mentioned that seq<'T> is F#'s name for IEnumerable<T>, and so the Seq module functions work on any IEnumerable, including ILists.