Added ocamldebug instruction section to the README

README.md

@@ -112,6 +112,34 @@ See issues
 [#196](https://github.com/c-cube/ocaml-containers/issues/196),
 [#197](https://github.com/c-cube/ocaml-containers/issues/197)
 
+## Debugging with `ocamldebug`
+
+To print values with types defined in `containers` in the bytecode debugger,
+you first have to load the appropriate bytecode archives. After starting a
+session, e.g. `ocamldebug your_program.bc`,
+```ocaml
+# load_printer containers_monomorphic.cma
+# load_printer containers.cma
+```
+For these archives to be found, you may have to `run` the program first. Now
+printing functions that have the appropriate type `Format.formatter -> 'a ->
+unit` can be installed. For example,
+```ocaml
+install_printer Containers.Int.pp
+```
+However, printer combinators are not easily handled by `ocamldebug`. For
+instance `install_printer Containers.(List.pp Int.pp)` will not work out of the
+box. You can make this work by writing a short module which defines ready-made
+combined printing functions, and loading that in ocamldebug. For instance
+```ocaml
+module M = struct let pp_int_list = Containers.(List.pp Int.pp) end
+```
+loaded via `load_printer m.cmo` and installed as `install_printer
+M.pp_int_list`.
+
+
+
+
 ## Change Log
 
 See [this file](./CHANGELOG.adoc).