diff --git a/src/FSharpPlus/Data/DList.fs b/src/FSharpPlus/Data/DList.fs
index eb33cbd01..db1702b24 100644
--- a/src/FSharpPlus/Data/DList.fs
+++ b/src/FSharpPlus/Data/DList.fs
@@ -271,7 +271,7 @@ module DList =
         DList<'T>.foldBack List.cons source []
     #else
         let mutable coll = new ListCollector<_> ()
-        iter coll.Add source
+        iter (fun x -> coll.Add x) source
         coll.Close ()
     #endif
 
@@ -281,7 +281,7 @@ module DList =
         source :> seq<'T> |> Seq.toArray
     #else
         let mutable coll = new ArrayCollector<_> ()
-        iter coll.Add source
+        iter (fun x -> coll.Add x) source
         coll.Close ()
     #endif