From b47da2396e60964f6440991efb59639bc5c11f61 Mon Sep 17 00:00:00 2001
From: Simon Cruanes <simon.cruanes.2007@m4x.org>
Date: Wed, 26 Jun 2024 11:02:14 -0400
Subject: [PATCH] feat fib: add `Private.cancel_from_outside`

---
 src/fib/fiber.ml  | 4 ++++
 src/fib/fiber.mli | 1 +
 2 files changed, 5 insertions(+)

diff --git a/src/fib/fiber.ml b/src/fib/fiber.ml
index c50325b1..b298c243 100644
--- a/src/fib/fiber.ml
+++ b/src/fib/fiber.ml
@@ -40,6 +40,10 @@ module Private_ = struct
     match A.get self.state with
     | Alive _ -> false
     | Terminating_or_done _ -> true
+
+  let cancel_from_outside (self : _ t) ebt : unit =
+    Fut.fulfill_idempotent (Fut.Private_.unsafe_promise_of_fut self.res)
+    @@ Error ebt
 end
 
 include Private_
diff --git a/src/fib/fiber.mli b/src/fib/fiber.mli
index d02c4e56..817f3967 100644
--- a/src/fib/fiber.mli
+++ b/src/fib/fiber.mli
@@ -31,6 +31,7 @@ module Private_ : sig
   type any = Any : _ t -> any [@@unboxed]
 
   val get_cur : unit -> any option
+  val cancel_from_outside : _ t -> Exn_bt.t -> unit
 end
 
 (**/**)