]> Hi, On Tue, Jan 07, 2003 at 02:57:10PM +1100, Pietro Abate wrote: > I have a problem expanding an <:expr<>> quotation. > the code snippet below raise this error > ocamlc -c -pp "camlp4o pa_extend.cmo q_MLast.cmo" -I > /usr/lib/ocaml/camlp4 test.ml > File "test.ml", line 19, characters 13-42: > This expression has type MLast.patt * ff but is here used with type > MLast.patt * MLast.expr You seem to mistake the "compiler" level and the "program" level. In the "compiler" (Camlp4) level, you need not define your type "ff" and its constructors A1 and A2: they belong actually to the "program" level. I mean: they need to be defined only in the files using your syntax extension test.cmo (compiled by camlp4o ./test.cmo ...) In the syntax tree, they cannot appear as things of type "tt" since Camlp4 cannot know all possible defined types. At this level, your constructor is just "syntax tree of a constructor" and the constructor name is just a string. The good method is: > el: > [[ n = LIDENT -> > let a = <:expr< A1 >> in > (<:patt<$lid:n$>>,<:expr<$a$>>) ]]; or: > el: > [[ n = LIDENT -> > (<:patt<$lid:n$>>,<:expr< A1 >>) ]]; or: > el: > [[ n = LIDENT -> > let a = "A1" in > (<:patt<$lid:n$>>,<:expr<$uid:a$>>) ]]; -- Daniel de RAUGLAUDRE http://cristal.inria.fr/~ddr/ ------------------- To unsubscribe, mail caml-list-request@inria.fr Archives: http://caml.inria.fr Bug reports: http://caml.inria.fr/bin/caml-bugs FAQ: http://caml.inria.fr/FAQ/ Beginner's list: http://groups.yahoo.com/group/ocaml_beginners