Mark resolvers contravariant

Resolves #458.
ocsigen · Mar 24, 2018 · a28d386 · a28d386
1 parent 25c40ee
commit a28d386
Showing 1 changed file with 1 addition and 1 deletion.
diff --git a/src/core/lwt.mli b/src/core/lwt.mli
@@ -410,7 +410,7 @@ type +'a t
     There is one exception to this: most promises can be {e canceled} by calling
     {!Lwt.cancel}, without going through a resolver. *)
 
-type 'a u
+type -'a u
 (** Resolvers for promises of type ['a ]{!Lwt.t}.
 
     Each resolver can be thought of as the {b write end} of one promise. It can