Calling IEnumerable.SelectMany

Question

Given this:

open System.Linq

let iota n = [0..(n-1)]

the following produces an error:

[2; 3; 4].SelectMany(fun n -> iota n)

Is there a way to pass function values to SelectMany?

Answer 1

You need to cast the result to a seq<int>:

[2; 3; 4].SelectMany(fun n -> iota n :> int seq)

alternatively you could use List.collect:

[2; 3; 4] |> List.collect iota