run_goal env loc name args goal
| Ast.ETactic (loc, name, args) ->
- (* All parameters of tactics must be simple expressions (strings,
- * in future booleans, numbers, etc).
+ (* All parameters of tactics must be simple constant expressions
+ * (strings, in future booleans, numbers, etc).
*)
let args = List.map (Ast.to_constant env) args in
run_tactic env loc name args
false (* XXX *)
(* Find the goal which matches the given tactic and run it.
- * const_args is a list of parameters (all constants).
+ * cargs is a list of parameters (all constants).
*)
-and run_tactic env loc tactic const_args =
- (* Search across all goals for a matching tactic. *)
+and run_tactic env loc tactic cargs =
+ (* Find all goals in the environment. Returns a list of (name, goal). *)
let goals =
let env = Ast.Env.bindings env in
filter_map
- (function (name, Ast.EGoal (loc, goal)) -> Some (name, goal) | _ -> None)
- env in
- let name, goal =
- (* If there are multiple goals matching, this must choose
- * the most recently defined (XXX).
- *)
- try
- List.find
- (fun (_, (_, patterns, _, _)) ->
- List.exists (matching_pattern env loc tactic const_args) patterns)
- goals
- with
- Not_found ->
- let tactic =
- Ast.ETactic (loc, tactic,
- List.map (fun c -> Ast.EConstant (loc, c))
- const_args) in
- failwithf "%a: don't know how to build %a"
- Ast.string_loc loc Ast.string_expr tactic in
-
- let args = [] (* XXX calculate free variables *) in
- run_goal env loc name args goal
-
-(* XXX This only does exact matches at the moment. *)
-and matching_pattern env loc tactic const_args = function
- | Ast.PTactic (loc, constructor, params)
- when tactic = constructor &&
- List.length const_args = List.length params ->
- (* Try to simplify the parameters of this pattern down
- * to constants, but don't fail here if we can't do this.
- *)
- (try
- let params = List.map (Ast.substitute env loc) params in
- let params = List.map (fun s -> Ast.CString s) params in
- const_args = params
- with Failure _ -> false
- )
+ (function
+ | name, Ast.EGoal (loc, goal) -> Some (name, goal)
+ | _ -> None) env in
+
+ (* Find all patterns. Returns a list of (pattern, name, goal). *)
+ let patterns : (Ast.pattern * Ast.id * Ast.goal) list =
+ List.flatten
+ (List.map (fun (name, ((_, patterns, _, _) as goal)) ->
+ List.map (fun pattern -> (pattern, name, goal)) patterns) goals) in
+
+ (* Find any patterns (ie. tactics) which match the one we
+ * are searching for. This returns a binding for the goal args,
+ * so we end up with a list of (pattern, name, goal, args).
+ *)
+ let patterns : (Ast.pattern * Ast.id * Ast.goal * Ast.expr list) list =
+ filter_map (
+ fun (pattern, name, ((params, _, _, _) as goal)) ->
+ match matching_pattern env loc tactic cargs pattern params with
+ | None -> None
+ | Some args -> Some (pattern, name, goal, args)
+ ) patterns in
+
+ let _, name, goal, args =
+ match patterns with
+ | [p] -> p
+ | [] ->
+ let t = Ast.ETactic (loc, tactic,
+ List.map (fun c -> Ast.EConstant (loc, c))
+ cargs) in
+ failwithf "%a: don't know how to build %a"
+ Ast.string_loc loc Ast.string_expr t
+ | _ ->
+ (* If there are multiple matching goals, then assuming the goals
+ * are different we must pick the one which was defined last in
+ * the file. However we don't do that right now. XXX
+ *)
+ assert false (* TODO! *) in
- | Ast.PTactic _ -> false
+ run_goal env loc name args goal
- | Ast.PVar (loc, name) -> assert false (* not implemented *)
+(* Test if pattern matches *tactic(cargs). If it does
+ * then we return Some args where args is the arguments that must
+ * be passed to the matching goal. The params parameter is
+ * the names of the parameters of that goal.
+ *)
+and matching_pattern env loc tactic cargs pattern params =
+ match pattern with
+ | Ast.PVar (loc, name) -> assert false (* TODO! *)
+ | Ast.PTactic (loc, ttactic, targs)
+ when tactic <> ttactic ||
+ List.length cargs <> List.length targs ->
+ None (* Can't possibly match if tactic name or #args is different. *)
+ | Ast.PTactic (loc, ttactic, targs) ->
+ (* Do the args match with a possible params binding? *)
+ try Some (matching_params env loc params targs cargs)
+ with Not_found -> None
+
+(* Return a possible binding. For example the goal is:
+ * goal compile (name) = "%name.o": "%name.c" {}
+ * which means that params = ["name"] and targs = ["%name.o"].
+ *
+ * If we are called with cargs = ["file1.o"], we would
+ * return ["file1"].
+ *
+ * On non-matching this raises Not_found.
+ *)
+and matching_params env loc params targs cargs =
+ (* This is going to record the resulting binding. *)
+ let res = ref Ast.Env.empty in
+ List.iter2 (matching_param env loc params res) targs cargs;
+ (* Rearrange the result into goal parameter order. Also this
+ * checks that every parameter got a binding.
+ *)
+ let res = !res in
+ List.map (
+ (* Allow the Not_found exception to escape if no binding for this param. *)
+ fun param -> Ast.Env.find param res
+ ) params
+
+(* If targ = "%name.o" and carg = "file.o" then this would set
+ * name => "file" in !res. If they don't match, raises Not_found.
+ *)
+and matching_param env loc params res targ carg =
+ match carg with
+ | Ast.CString carg ->
+ (* Substitute any non parameters in targ from the environment. *)
+ let targ =
+ List.map (
+ function
+ | Ast.SString _ as s -> s
+ | Ast.SVar name ->
+ if not (List.mem name params) then (
+ try
+ let expr = Ast.getvar env loc name in
+ match Ast.to_constant env expr with
+ | Ast.CString s -> Ast.SString s
+ with Failure _ -> raise Not_found
+ )
+ else
+ Ast.SVar name
+ ) targ in
+
+ (* Do the actual pattern matching. Any remaining SVar elements
+ * must refer to goal parameters.
+ *)
+ let carg = ref carg in
+ let rec loop = function
+ | [] ->
+ (* End of targ, we must have matched all of carg. *)
+ if !carg <> "" then raise Not_found
+ | Ast.SString s :: rest ->
+ (* Does this match the first part of !carg? *)
+ let clen = String.length !carg in
+ let slen = String.length s in
+ if slen > clen || s <> String.sub !carg 0 slen then
+ raise Not_found;
+ (* Yes, so continue after the matching prefix. *)
+ carg := String.sub !carg slen (clen-slen);
+ loop rest
+ | Ast.SVar name :: Ast.SString s :: rest ->
+ (* This is a goal parameter. Find s later in !carg. *)
+ let i = string_find !carg s in
+ if i = -1 then raise Not_found;
+ (* Set the binding in !res. *)
+ let r = Ast.EConstant (Ast.noloc,
+ Ast.CString (String.sub !carg 0 i)) in
+ res := Ast.Env.add name r !res;
+ (* Continue after the match. *)
+ let skip = i + String.length s in
+ carg := String.sub !carg skip (String.length !carg - skip);
+ loop rest
+ | Ast.SVar name :: [] ->
+ (* Matches the whole remainder of the string. *)
+ let r = Ast.EConstant (Ast.noloc, Ast.CString !carg) in
+ res := Ast.Env.add name r !res
+ | Ast.SVar x :: Ast.SVar y :: _ ->
+ (* TODO! We cannot match a target like "%x%y". *)
+ assert false
+ in
+ loop targ