unikernel/duniverse/ppxlib/test/error_embedding/extender.ml

@@ -0,0 +1,15 @@
+open Ppxlib
+
+let export_string ~ctxt e =
+  let loc = Expansion_context.Extension.extension_point_loc ctxt in
+  let open Ast_builder.Default in
+  estring ~loc e
+
+let export_string_extension =
+  Extension.V3.declare "export_string" Extension.Context.expression
+    Ast_pattern.(single_expr_payload (estring __))
+    export_string
+
+let rule = Ppxlib.Context_free.Rule.extension export_string_extension
+let () = Driver.register_transformation ~rules:[ rule ] "export_string"
+let () = Driver.standalone ()