ocaml/camlp4/etc/pr_extfun.ml

93 lines
2.7 KiB
OCaml

(* camlp4r q_MLast.cmo ./pa_extfun.cmo *)
(* $Id$ *)
open Pcaml;
open Spretty;
value loc = (0, 0);
value expr e dg k = pr_expr.pr_fun "top" e dg k;
value patt e dg k = pr_patt.pr_fun "top" e dg k;
value rec un_extfun rpel =
fun
[ <:expr< [ ($_$, $_$, fun [ $list:pel$ ]) :: $el$ ] >> ->
let (p, wo, e) =
match pel with
[ [(p, wo, <:expr< Some $e$ >>);
(<:patt< _ >>, None, <:expr< None >>)] ->
(p, wo, e)
| [(p, wo, <:expr< Some $e$ >>)] -> (p, wo, e)
| _ -> raise Not_found ]
in
let rpel =
match rpel with
[ [(p1, wo1, e1) :: pel] ->
if wo1 = wo && e1 = e then
let p =
match (p1, p) with
[ (<:patt< ($x1$ as $x2$) >>, <:patt< ($y1$ as $y2$) >>) ->
if x2 = y2 then <:patt< ($x1$ | $y1$ as $x2$) >>
else <:patt< $p1$ | $p$ >>
| _ -> <:patt< $p1$ | $p$ >> ]
in
[(p, wo, e) :: pel]
else [(p, wo, e) :: rpel]
| [] -> [(p, wo, e)] ]
in
un_extfun rpel el
| <:expr< [] >> -> List.rev rpel
| _ -> raise Not_found ]
;
value rec listwbws elem b sep el k =
match el with
[ [] -> [: b; k :]
| [x] -> [: `elem b x k :]
| [x :: l] -> [: `elem b x [: :]; listwbws elem [: `sep :] sep l k :] ]
;
value rec match_assoc_list pwel k =
match pwel with
[ [pwe] -> match_assoc [: `S LR "[" :] pwe [: `S LR "]"; k :]
| pel ->
Vbox
[: `HVbox [: :];
listwbws match_assoc [: `S LR "[" :] (S LR "|") pel
[: `S LR "]"; k :] :] ]
and match_assoc b (p, w, e) k =
let s =
let (p, k) =
match p with
[ <:patt< ($p$ as $p2$) >> -> (p, [: `S LR "as"; `patt p2 "" [: :] :])
| _ -> (p, [: :]) ]
in
match w with
[ Some e1 ->
[: `HVbox
[: `HVbox [: :]; `patt p "" k;
`HVbox [: `S LR "when"; `expr e1 "" [: `S LR "->" :] :] :] :]
| _ -> [: `patt p "" [: k; `S LR "->" :] :] ]
in
HVbox [: b; `HVbox [: `HVbox s; `expr e "" k :] :]
;
let lev = find_pr_level "top" pr_expr.pr_levels in
lev.pr_rules :=
extfun lev.pr_rules with
[ <:expr< Extfun.extend $e$ $list$ >> as ge ->
fun curr next dg k ->
try
let pel = un_extfun [] list in
[: `HVbox [: :];
`BEbox [: `S LR "extfun"; `expr e "" [: :]; `S LR "with" :];
`match_assoc_list pel k :]
with
[ Not_found -> [: `next ge dg k :] ] ];
let lev = find_pr_level "apply" pr_expr.pr_levels in
lev.pr_rules :=
extfun lev.pr_rules with
[ <:expr< Extfun.extend $e$ $list$ >> as ge ->
fun curr next dg k -> [: `next ge dg k :] ];