2 files changed, 8 insertions, 0 deletions
diff --git a/lib/kernel/Lifecycle.ml b/lib/kernel/Lifecycle.ml
index bf0b544..ac6bb20 100644
--- a/lib/kernel/Lifecycle.ml
+++ b/lib/kernel/Lifecycle.ml
@@ -14,6 +14,13 @@ class null =
     method release = ()
   end
 
+class exclusive =
+  object
+    val taken = Atomic.make false
+    method reference = Atomic.compare_and_set taken false true
+    method release = Atomic.set taken false
+  end
+
 class virtual counted =
   object (self)
     val references = Atomic.make 1
diff --git a/lib/kernel/Lifecycle.mli b/lib/kernel/Lifecycle.mli
index fa3abee..d4ef178 100644
--- a/lib/kernel/Lifecycle.mli
+++ b/lib/kernel/Lifecycle.mli
@@ -9,6 +9,7 @@ class type virtual controlled_lifecycle = object
 end
 
 class null : lifecycle
+class exclusive : lifecycle
 class virtual counted : controlled_lifecycle
 
 (** stands for [inner], carrying what it carries, while holding a