I finally have my own solution.

So am I ready to become the director of the Ocaml Project at INRIA in
France?   :-)    Well maybe not, but I'm proud of this.  It took some
practice to finally figure this out.  Definitely a challenging language!
But the code is pretty compact, which is an appealing characteristic of the
language.  And even if I never use Ocaml professionally, it's fun because
it's really helping me to understand how recursion works.  I also like the
idea of embedding recursive functions inside non-recursive functions.
Pretty interesting stuff for sure!

*let pack list = *

*let rec pack_ l sub out =  *

*match l with *

*|[ ] -> !out*

*|head :: tail -> if tail = [ ] then begin sub := [head] @ !sub; out:= !sub
:: !out; List.rev !out end *

*else if head = ( List.hd tail ) then begin sub := [head] @ !sub ; pack_ (
List.tl l ) sub out end *

*else begin sub := [head] @ !sub ; out := !sub :: !out ; pack_ ( List.tl l
) ( ref [ ] ) out end *

*in *

*pack_ list ( ref [ ] ) ( ref [ ] ) ;; *


Best,


Douglas.