move directory out of prototype

1 files changed, 11 insertions, 0 deletions

diff --git a/lib/protocols/Directory.ml b/lib/protocols/Directory.ml
index 232a47e..b8caca0 100644
--- a/lib/protocols/Directory.ml
+++ b/lib/protocols/Directory.ml
@@ -10,3 +10,14 @@ let make impl = Directory (impl :> implementation)
 let from handle = Handle.into handle (function Directory impl -> Some impl | _ -> None)
 let list i = Handle.invoke i (fun o -> o#list)
 let find i name = Handle.invoke i (fun o -> o#find name)
+
+let children directory =
+  let open Utilities.Result in
+  let* listing = Handle.require from directory in
+  let* names = list listing in
+  BatFingerTree.to_list names
+  |> List.map (fun name ->
+      let* found = find listing name in
+      Ok (Option.map (fun child -> name, child) found) )
+  |> Utilities.List.sequence
+  |> Result.map (List.filter_map Fun.id)