From 342335abe99fde2bfd4a8f086b93cd6ee3708319 Mon Sep 17 00:00:00 2001
From: Christian Luksch <luksch@vrvis.at>
Date: Wed, 18 Sep 2024 14:37:02 +0200
Subject: [PATCH] Index: Monitor.Enter/Exit in all places

---
 .../Datastructures/Index.fs                    | 18 ++++++++++--------
 1 file changed, 10 insertions(+), 8 deletions(-)

diff --git a/src/FSharp.Data.Adaptive/Datastructures/Index.fs b/src/FSharp.Data.Adaptive/Datastructures/Index.fs
index 3a0161b..85ec2e8 100644
--- a/src/FSharp.Data.Adaptive/Datastructures/Index.fs
+++ b/src/FSharp.Data.Adaptive/Datastructures/Index.fs
@@ -163,16 +163,18 @@ type Index private(real : IndexNode) =
     member private x.Value = real
 
     member x.After() =
-        lock real (fun () ->
+        Monitor.Enter real
+        let res =
             let next = real.Next
             if next <> real.Root then 
-                lock next (fun () ->
-                    next.RefCount <- next.RefCount + 1
-                )
+                Monitor.Enter next 
+                next.RefCount <- next.RefCount + 1
+                Monitor.Exit next
                 next |> Index
             else 
                 real.InsertAfter() |> Index
-        )   
+        Monitor.Exit real
+        res
 
     member x.Before() =
         let prev = real.Prev
@@ -200,9 +202,9 @@ type Index private(real : IndexNode) =
             if next = r then 
                 l.InsertAfter() |> Index
             else
-                lock next (fun () ->
-                    next.RefCount <- next.RefCount + 1
-                )
+                Monitor.Enter next
+                next.RefCount <- next.RefCount + 1
+                Monitor.Exit next
                 next |> Index
         
         Monitor.Exit l