Re: [Caml-list] How to Create Sensible Debugging Information when Dynamically Typechecking Code Generated with camlp5 Quotations

[Daniel de Rauglaudre <daniel.de_rauglaudre@inria.fr>]

Hi,

On Tue, Dec 18, 2007 at 03:05:05PM -0800, echinuz echinuz wrote:

> That seems to have done the trick.  Thanks for adding that function.
> The overall solution is a little awkward, so if you take requests,
> it would be nice if this process is streamlined in future versions.
> In other words, it would be nice if there was an easier way to pass
> through location information into the final AST and an easier way to
> throw errors with this information.

Ok, but I don't see, for the moment, what kind of function I can offer.

In the meantime, you can improve your code by building the functions:

  let make_expr_loc loc =
    let line_nb,bol_pos,bp,ep = get_loc loc in
    <:expr<
      (Ploc.make $int:line_nb$ $int:bol_pos$ ($int:bp$, $int:ep$),
       $str:!Pcaml.input_file$)
    >>
  ;;
  let make_patt_loc loc =
    let line_nb,bol_pos,bp,ep = get_loc loc in
    <:patt<
      (Ploc.make $int:line_nb$ $int:bol_pos$ ($int:bp$, $int:ep$),
       $str:!Pcaml.input_file$)
    >>
  ;;

and, therefore, your:

     | PInt (loc,x)->
         let line_nb,bol_pos,bp,ep=get_loc loc in
         <:expr< Alg.Int (
             (Ploc.make$int:line_nb$ $int:bol_pos$ ($int:bp$,$int:ep$),
             $str:!Pcaml.input_file$),
             $int:x$) >>

can be written:

    | PInt (loc,x)->
        <:expr< Alg.Int ($make_expr_loc loc$, $int:x$) >>

For antiquotations, notice that you can use named antiquotations. For
example, adding a case, in your grammar:

        | x=ANTIQUOT "int"-> ...

allowing you to use $int:expr$ in your quotations, for an expression
of type int, and you can generate the good code with Alg.Int and a
correctly shifted location (without forgetting the "$int:" before the
expression). You can add a case for floats, and so on.

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