Hi,

> 2. What is the simplest way of replacing (not extending) Ocaml's
> grammar using Camlp5 ? Or equivalently, if I have a parser that
> generates Ocaml AST using q_MLast, how do I do to feed that to
> the Ocaml compiler?

I added a (small) chapter about how to make one's syntax for OCaml
using Camlp5. This chapter will be in next version (5.16) but you
can see it there:
   http://pauillac.inria.fr/~ddr/camlp5/doc/html/redef.html

For the current Camlp5 version (5.15), this part works except that
you have to compile the file "mysyntax.ml" (of that chapter) by:
    ocamlc -pp "camlp5r pa_extend.cmo q_MLast.cmo" -I $(camlp5 -where) -c mysyntax.ml

-- 
Daniel de Rauglaudre
http://pauillac.inria.fr/~ddr/