small refactor

Author: c-cube

src/core/fut.ml

@@ -431,8 +431,7 @@ let await (self : 'a t) : 'a =
   | exception C.Running ->
     let trigger = Trigger.create () in
     (* suspend until the future is resolved *)
-    if C.try_attach self trigger then
-      Option.iter Exn_bt.raise @@ Trigger.await trigger;
+    if C.try_attach self trigger then Trigger.await_exn trigger;
 
     (* un-suspended: we should have a result! *)
     get_or_fail_exn self

src/forkjoin/moonpool_forkjoin.ml

@@ -64,7 +64,7 @@ module State_ = struct
       done;
 
       (* wait for the other computation to be done *)
-      if !must_await then Trigger.await trigger |> Option.iter Exn_bt.raise
+      if !must_await then Trigger.await_exn trigger
     | Right_solved _ | Both_solved _ -> assert false
 end
 
@@ -144,7 +144,7 @@ let for_ ?chunk_size n (f : int -> int -> unit) : unit =
       i := !i + len_range
     done;
 
-    Trigger.await trigger |> Option.iter Exn_bt.raise;
+    Trigger.await_exn trigger;
     Option.iter Exn_bt.raise @@ A.get failure;
     ()
   )