36 lines
954 B
OCaml
36 lines
954 B
OCaml
|
(* camlp4r *)
|
||
|
|
(* $Id$ *)
|
||
|
|
|
||
|
|
(* Module [Extfun]: extensible functions *)
|
||
|
|
|
||
|
|
(* This module implements pattern matching extensible functions.
|
||
|
|
To extend, use syntax [pa_extfun.cmo]:
|
||
|
|
- [extfun e with [ pattern_matching ]] *)
|
||
|
|
|
||
|
|
type t 'a 'b = 'x;
|
||
|
|
(* The type of the extensible functions of type ['a -> 'b] *)
|
||
|
|
value empty : t 'a 'b;
|
||
|
|
(* Empty extensible function *)
|
||
|
|
value apply : t 'a 'b -> 'a -> 'b;
|
||
|
|
(* Apply an extensible function *)
|
||
|
|
exception Failure;
|
||
|
|
(* Match failure while applying an extensible function *)
|
||
|
|
value print : t 'a 'b -> unit;
|
||
|
|
(* Print patterns in the order they are recorded *)
|
||
|
|
|
||
|
|
(*--*)
|
||
|
|
|
||
|
|
type matching 'a 'b = { patt : patt; has_when : bool; expr : expr 'a 'b }
|
||
|
|
and patt =
|
||
|
|
[ Eapp of list patt
|
||
|
|
| Eacc of list patt
|
||
|
|
| Econ of string
|
||
|
|
| Estr of string
|
||
|
|
| Eint of string
|
||
|
|
| Etup of list patt
|
||
|
|
| Evar of unit ]
|
||
|
|
and expr 'a 'b = 'a -> option 'b
|
||
|
|
;
|
||
|
|
|
||
|
|
value extend : t 'a 'b -> list (patt * bool * expr 'a 'b) -> t 'a 'b;
|