list.iterate

Stream: Is there code for X?

[Yakov Pechersky]

Do we have something already that does this?

variables {α : Type*}

def list.iterate (f : α → α) : α → ℕ → list α
| x 0       := []
| x (n + 1) := x :: list.iterate (f x) n

[Alex J. Best]

There is docs#stream.iterate and docs#stream.approx

[Eric Wieser]

Can this be built from docs#list.scanl and docs#list.repeat?

[Eric Wieser]

(repeat f n).scanl id init seems like it would work