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1 files changed, 15 insertions, 1 deletions

diff --git a/src/Values.ml b/src/Values.ml
index 7b5e9537..9a932fc2 100644
--- a/src/Values.ml
+++ b/src/Values.ml
@@ -346,7 +346,21 @@ type abs = {
     which are a special kind of value.
 *)
 
-class virtual ['self] map_g_value =
+(** Monomorphic version of the map visitor for [g_typed_value].
+
+    The type variables are quantified at the level of the class (not at the
+    level of each method). As a consequence, the visit methods don't need to
+    take closures as parameters.
+
+    The polymorphic visitor generated by the visitors macro caused some
+    trouble: it was in some cases not possible to override a function
+    to refine the behaviour of a visitor. With this version, it is
+    possible. Note that this works only because the polymorphism of
+    [g_value], [g_adt_value], etc. is "uniform": the type instantiation
+    is always the same.
+
+*)
+class virtual ['self] map_g_typed_value =
   object (self : 'self)
     inherit [_] VisitorsRuntime.map