(* This file is part of the Catala compiler, a specification language for tax and social benefits computation rules. Copyright (C) 2020 Inria, contributor: Denis Merigoux Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at http://www.apache.org/licenses/LICENSE-2.0 Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License. *) open Catala_utils open Shared_ast type scope_var_ctx = { scope_var_name : ScopeVar.t; scope_var_typ : naked_typ; scope_var_io : Desugared.Ast.io; } type scope_input_var_ctx = { scope_input_name : StructField.t; scope_input_io : Runtime.io_input Mark.pos; scope_input_typ : naked_typ; } type 'm scope_sig_ctx = { scope_sig_local_vars : scope_var_ctx list; (** List of scope variables *) scope_sig_scope_var : 'm Ast.expr Var.t; (** Var representing the scope *) scope_sig_input_var : 'm Ast.expr Var.t; (** Var representing the scope input inside the scope func *) scope_sig_input_struct : StructName.t; (** Scope input *) scope_sig_output_struct : StructName.t; (** Scope output *) scope_sig_in_fields : scope_input_var_ctx ScopeVar.Map.t; (** Mapping between the input scope variables and the input struct fields. *) scope_sig_out_fields : StructField.t ScopeVar.Map.t; (** Mapping between the output scope variables and the output struct fields. TODO: could likely be removed now that we have it in the program ctx *) } type 'm scope_sigs_ctx = 'm scope_sig_ctx ScopeName.Map.t type 'm ctx = { structs : struct_ctx; enums : enum_ctx; scope_name : ScopeName.t option; scopes_parameters : 'm scope_sigs_ctx; toplevel_vars : ('m Ast.expr Var.t * naked_typ) TopdefName.Map.t; scope_vars : ('m Ast.expr Var.t * naked_typ * Desugared.Ast.io) ScopeVar.Map.t; subscope_vars : ('m Ast.expr Var.t * naked_typ * Desugared.Ast.io) ScopeVar.Map.t SubScopeName.Map.t; date_rounding : date_rounding; } let mark_tany m pos = Expr.with_ty m (Mark.add pos TAny) ~pos (* Expression argument is used as a type witness, its type and positions aren't used *) let pos_mark_mk (type a m) (e : (a, m) gexpr) : (Pos.t -> m mark) * ((_, Pos.t) Mark.ed -> m mark) = let pos_mark pos = Expr.map_mark (fun _ -> pos) (fun _ -> TAny, pos) (Mark.get e) in let pos_mark_as e = pos_mark (Mark.get e) in pos_mark, pos_mark_as let merge_defaults ~(is_func : bool) (caller : (dcalc, 'm) boxed_gexpr) (callee : (dcalc, 'm) boxed_gexpr) : (dcalc, 'm) boxed_gexpr = (* the merging of the two defaults, from the reentrant caller and the callee, is straightfoward in the general case and a little subtler when the variable being defined is a function. *) if is_func then let m_callee = Mark.get callee in let unboxed_callee = Expr.unbox callee in match Mark.remove unboxed_callee with | EAbs { binder; tys } -> let vars, body = Bindlib.unmbind binder in let m_body = Mark.get body in let caller = let m = Mark.get caller in let pos = Expr.mark_pos m in Expr.make_app caller (List.map2 (fun (var : (dcalc, 'm) naked_gexpr Bindlib.var) ty -> Expr.evar var (* we have to correctly propagate types when doing this rewriting *) (Expr.with_ty m_body ~pos:(Expr.mark_pos m_body) ty)) (Array.to_list vars) tys) pos in let ltrue = Expr.elit (LBool true) (Expr.with_ty m_callee (Mark.add (Expr.mark_pos m_callee) (TLit TBool))) in let d = Expr.edefault [caller] ltrue (Expr.rebox body) m_body in Expr.make_abs vars (Expr.eerroronempty d m_body) tys (Expr.mark_pos m_callee) | _ -> assert false (* should not happen because there should always be a lambda at the beginning of a default with a function type *) else let caller = let m = Mark.get caller in let pos = Expr.mark_pos m in Expr.make_app caller [Expr.elit LUnit (Expr.with_ty m (Mark.add pos (TLit TUnit)))] pos in let body = let m = Mark.get callee in let ltrue = Expr.elit (LBool true) (Expr.with_ty m (Mark.add (Expr.mark_pos m) (TLit TBool))) in Expr.eerroronempty (Expr.edefault [caller] ltrue callee m) m in body let tag_with_log_entry (e : 'm Ast.expr boxed) (l : log_entry) (markings : Uid.MarkedString.info list) : 'm Ast.expr boxed = let m = mark_tany (Mark.get e) (Expr.pos e) in if Cli.globals.trace then Expr.eapp (Expr.eop (Log (l, markings)) [TAny, Expr.pos e] m) [e] m else e (* In a list of exceptions, it is normally an error if more than a single one apply at the same time. This relaxes this constraint slightly, allowing a conflict if all the triggered conflicting exception yield syntactically equal results (and as long as none of these exceptions have exceptions themselves) NOTE: the choice of the exception that will be triggered and show in the trace is arbitrary (but deterministic). *) let collapse_similar_outcomes (type m) (excepts : m Scopelang.Ast.expr list) : m Scopelang.Ast.expr list = let module ExprMap = Map.Make (struct type t = m Scopelang.Ast.expr let compare = Expr.compare let format = Expr.format end) in let cons_map = List.fold_left (fun map -> function | (EDefault { excepts = []; cons; _ }, _) as e -> ExprMap.update cons (fun prev -> Some (e :: Option.value ~default:[] prev)) map | _ -> map) ExprMap.empty excepts in let _, excepts = List.fold_right (fun e (cons_map, excepts) -> match e with | EDefault { excepts = []; cons; _ }, _ -> let collapsed_exc = List.fold_left (fun acc -> function | EDefault { excepts = []; just; cons }, pos -> [EDefault { excepts = acc; just; cons }, pos] | _ -> assert false) [] (ExprMap.find cons cons_map) in ExprMap.add cons [] cons_map, collapsed_exc @ excepts | e -> cons_map, e :: excepts) excepts (cons_map, []) in excepts let thunk_scope_arg ~is_func io_in e = (* For "context" (or reentrant) variables, we thunk them as [(fun () -> e)] so that we can put them in default terms at the initialisation of the function body, allowing an empty error to recover the default value. *) let silent_var = Var.make "_" in let pos = Mark.get io_in in match Mark.remove io_in with | Runtime.NoInput -> invalid_arg "thunk_scope_arg" | Runtime.OnlyInput -> Expr.eerroronempty e (Mark.get e) | Runtime.Reentrant -> (* we don't need to thunk expressions that are already functions *) if is_func then e else Expr.make_abs [| silent_var |] e [TLit TUnit, pos] pos let rec translate_expr (ctx : 'm ctx) (e : 'm Scopelang.Ast.expr) : 'm Ast.expr boxed = let m = Mark.get e in match Mark.remove e with | EMatch { e = e1; name; cases = e_cases } -> let enum_sig = EnumName.Map.find name ctx.enums in let d_cases, remaining_e_cases = (* FIXME: these checks should probably be moved to a better place *) EnumConstructor.Map.fold (fun constructor _ (d_cases, e_cases) -> let case_e = try EnumConstructor.Map.find constructor e_cases with Not_found -> Message.raise_spanned_error (Expr.pos e) "The constructor %a of enum %a is missing from this pattern \ matching" EnumConstructor.format constructor EnumName.format name in let case_d = translate_expr ctx case_e in ( EnumConstructor.Map.add constructor case_d d_cases, EnumConstructor.Map.remove constructor e_cases )) enum_sig (EnumConstructor.Map.empty, e_cases) in if not (EnumConstructor.Map.is_empty remaining_e_cases) then Message.raise_spanned_error (Expr.pos e) "Pattern matching is incomplete for enum %a: missing cases %a" EnumName.format name (EnumConstructor.Map.format_keys ~pp_sep:(fun fmt () -> Format.fprintf fmt ", ")) remaining_e_cases; let e1 = translate_expr ctx e1 in Expr.ematch e1 name d_cases m | EScopeCall { scope; args } -> let pos = Expr.mark_pos m in let sc_sig = ScopeName.Map.find scope ctx.scopes_parameters in let in_var_map = ScopeVar.Map.merge (fun var_name (str_field : scope_input_var_ctx option) expr -> let expr = match str_field, expr with | Some { scope_input_io = Reentrant, _; _ }, None -> Some (Expr.unbox (Expr.eemptyerror (mark_tany m pos))) | _ -> expr in match str_field, expr with | None, None -> None | Some var_ctx, Some e -> Some ( var_ctx.scope_input_name, thunk_scope_arg ~is_func: (match var_ctx.scope_input_typ with | TArrow _ -> true | _ -> false) var_ctx.scope_input_io (translate_expr ctx e) ) | Some var_ctx, None -> Message.raise_multispanned_error [ None, pos; ( Some "Declaration of the missing input variable", Mark.get (StructField.get_info var_ctx.scope_input_name) ); ] "Definition of input variable '%a' missing in this scope call" ScopeVar.format var_name | None, Some _ -> Message.raise_multispanned_error [ None, pos; ( Some "Declaration of scope '%a'", Mark.get (ScopeName.get_info scope) ); ] "Unknown input variable '%a' in scope call of '%a'" ScopeVar.format var_name ScopeName.format scope) sc_sig.scope_sig_in_fields args in let field_map = ScopeVar.Map.fold (fun _ (fld, e) acc -> StructField.Map.add fld e acc) in_var_map StructField.Map.empty in let arg_struct = Expr.estruct sc_sig.scope_sig_input_struct field_map (mark_tany m pos) in let called_func = tag_with_log_entry (Expr.evar sc_sig.scope_sig_scope_var (mark_tany m pos)) BeginCall [ScopeName.get_info scope; Mark.add (Expr.pos e) "direct"] in let single_arg = tag_with_log_entry arg_struct (VarDef { log_typ = TStruct sc_sig.scope_sig_input_struct; log_io_output = false; log_io_input = OnlyInput; }) [ ScopeName.get_info scope; Mark.add (Expr.pos e) "direct"; Mark.add (Expr.pos e) "input"; ] in let direct_output_info = [ ScopeName.get_info scope; Mark.add (Expr.pos e) "direct"; Mark.add (Expr.pos e) "output"; ] in (* calling_expr = scope_function scope_input_struct *) let calling_expr = Expr.eapp called_func [single_arg] m in (* For the purposes of log parsing explained in Runtime.EventParser, we need to wrap this function call in a flurry of log tags. Specifically, we are mascarading this scope call as a function call. In a normal function call, the log parser expects the output of the function to be defined as a default, hence the production of the output should yield a PosRecordIfTrueBool (which is not the case here). To remedy this absence we fabricate a fake PosRecordIfTrueBool attached to a silent let binding to "true" before returning the output value. But this is not sufficient. Indeed for the tricky case of [tests/test_scope/scope_call3.catala_en], when a scope returns a function, because we insert loggins calls at the call site of the function and not during its definition, then we're missing the call log instructions of the function returned. To avoid this trap, we need to rebind the resulting scope output struct by eta-expanding the functions to insert logging instructions. *) let result_var = Var.make "result" in let result_eta_expanded_var = Var.make "result" in (* result_eta_expanded = { struct_output_function_field = lambda x -> log (struct_output.struct_output_function_field x) ... } *) let result_eta_expanded = Expr.estruct sc_sig.scope_sig_output_struct (StructField.Map.mapi (fun field typ -> let original_field_expr = Expr.estructaccess (Expr.make_var result_var (Expr.with_ty m (TStruct sc_sig.scope_sig_output_struct, Expr.pos e))) field sc_sig.scope_sig_output_struct (Expr.with_ty m typ) in match Mark.remove typ with | TArrow (ts_in, t_out) -> (* Here the output scope struct field is a function so we eta-expand it and insert logging instructions. Invariant: works because there is no partial evaluation. *) let params_vars = ListLabels.mapi ts_in ~f:(fun i _ -> Var.make ("param" ^ string_of_int i)) in let f_markings = [ScopeName.get_info scope; StructField.get_info field] in Expr.make_abs (Array.of_list params_vars) (tag_with_log_entry (tag_with_log_entry (Expr.eapp (tag_with_log_entry original_field_expr BeginCall f_markings) (ListLabels.mapi (List.combine params_vars ts_in) ~f:(fun i (param_var, t_in) -> tag_with_log_entry (Expr.make_var param_var (Expr.with_ty m t_in)) (VarDef { log_typ = Mark.remove t_in; log_io_output = false; log_io_input = OnlyInput; }) (f_markings @ [ Mark.add (Expr.pos e) ("input" ^ string_of_int i); ]))) (Expr.with_ty m t_out)) (VarDef { log_typ = Mark.remove t_out; log_io_output = true; log_io_input = NoInput; }) (f_markings @ [Mark.add (Expr.pos e) "output"])) EndCall f_markings) ts_in (Expr.pos e) | _ -> original_field_expr) (StructName.Map.find sc_sig.scope_sig_output_struct ctx.structs)) (Expr.with_ty m (TStruct sc_sig.scope_sig_output_struct, Expr.pos e)) in (* Here we have to go through an if statement that records a decision being taken with a log. We can't just do a let-in with the true boolean value enclosed in the log because it might get optimized by a compiler later down the chain. *) (* if_then_else_returned = if log true then result_eta_expanded else result_eta_expanded *) let if_then_else_returned = Expr.eifthenelse (tag_with_log_entry (Expr.box (Mark.add (Expr.with_ty m (TLit TBool, Expr.pos e)) (ELit (LBool true)))) PosRecordIfTrueBool direct_output_info) (Expr.make_var result_eta_expanded_var (Expr.with_ty m (TStruct sc_sig.scope_sig_output_struct, Expr.pos e))) (Expr.make_var result_eta_expanded_var (Expr.with_ty m (TStruct sc_sig.scope_sig_output_struct, Expr.pos e))) (Expr.with_ty m (TStruct sc_sig.scope_sig_output_struct, Expr.pos e)) in (* let result_var = calling_expr in let result_eta_expanded_var = result_eta_expaneded in log (if_then_else_returned ) *) Expr.make_let_in result_var (TStruct sc_sig.scope_sig_output_struct, Expr.pos e) calling_expr (Expr.make_let_in result_eta_expanded_var (TStruct sc_sig.scope_sig_output_struct, Expr.pos e) result_eta_expanded (tag_with_log_entry (tag_with_log_entry if_then_else_returned (VarDef { log_typ = TStruct sc_sig.scope_sig_output_struct; log_io_output = true; log_io_input = NoInput; }) direct_output_info) EndCall [ScopeName.get_info scope; Mark.add (Expr.pos e) "direct"]) (Expr.pos e)) (Expr.pos e) | EApp { f; args } -> (* We insert various log calls to record arguments and outputs of user-defined functions belonging to scopes *) let e1_func = translate_expr ctx f in let markings = match ctx.scope_name, Mark.remove f with | Some sname, ELocation loc -> ( match loc with | ScopelangScopeVar (v, _) -> [ScopeName.get_info sname; ScopeVar.get_info v] | SubScopeVar (s, _, (v, _)) -> [ScopeName.get_info s; ScopeVar.get_info v] | ToplevelVar _ -> []) | _ -> [] in let e1_func = match markings with | [] -> e1_func | m -> tag_with_log_entry e1_func BeginCall m in let new_args = List.map (translate_expr ctx) args in let input_typs, output_typ = (* NOTE: this is a temporary solution, it works because it's assume that all function calls are from scope variable. However, this will change -- for more information see https://github.com/CatalaLang/catala/pull/280#discussion_r898851693. *) let retrieve_in_and_out_typ_or_any var vars = let _, typ, _ = ScopeVar.Map.find (Mark.remove var) vars in match typ with | TArrow (marked_input_typ, marked_output_typ) -> List.map Mark.remove marked_input_typ, Mark.remove marked_output_typ | _ -> ListLabels.map new_args ~f:(fun _ -> TAny), TAny in match Mark.remove f with | ELocation (ScopelangScopeVar var) -> retrieve_in_and_out_typ_or_any var ctx.scope_vars | ELocation (SubScopeVar (_, sname, var)) -> ctx.subscope_vars |> SubScopeName.Map.find (Mark.remove sname) |> retrieve_in_and_out_typ_or_any var | ELocation (ToplevelVar tvar) -> ( let _, typ = TopdefName.Map.find (Mark.remove tvar) ctx.toplevel_vars in match typ with | TArrow (tin, (tout, _)) -> List.map Mark.remove tin, tout | _ -> Message.raise_spanned_error (Expr.pos e) "Application of non-function toplevel variable") | _ -> ListLabels.map new_args ~f:(fun _ -> TAny), TAny in (* Message.emit_debug "new_args %d, input_typs: %d, input_typs %a" (List.length new_args) (List.length input_typs) (Format.pp_print_list Print.typ_debug) (List.map (Mark.add Pos.no_pos) input_typs); *) let new_args = ListLabels.mapi (List.combine new_args input_typs) ~f:(fun i (new_arg, input_typ) -> match markings with | _ :: _ as m -> tag_with_log_entry new_arg (VarDef { log_typ = input_typ; log_io_output = false; log_io_input = OnlyInput; }) (m @ [Mark.add (Expr.pos e) ("input" ^ string_of_int i)]) | _ -> new_arg) in let new_e = Expr.eapp e1_func new_args m in let new_e = match markings with | [] -> new_e | m -> tag_with_log_entry (tag_with_log_entry new_e (VarDef { log_typ = output_typ; log_io_output = true; log_io_input = NoInput; }) (m @ [Mark.add (Expr.pos e) "output"])) EndCall m in new_e | EDefault { excepts; just; cons } -> let excepts = collapse_similar_outcomes excepts in Expr.edefault (List.map (translate_expr ctx) excepts) (translate_expr ctx just) (translate_expr ctx cons) m | ELocation (ScopelangScopeVar a) -> let v, _, _ = ScopeVar.Map.find (Mark.remove a) ctx.scope_vars in Expr.evar v m | ELocation (SubScopeVar (_, s, a)) -> ( try let v, _, _ = ScopeVar.Map.find (Mark.remove a) (SubScopeName.Map.find (Mark.remove s) ctx.subscope_vars) in Expr.evar v m with Not_found -> Message.raise_multispanned_error [ Some "Incriminated variable usage:", Expr.pos e; ( Some "Incriminated subscope variable declaration:", Mark.get (ScopeVar.get_info (Mark.remove a)) ); ( Some "Incriminated subscope declaration:", Mark.get (SubScopeName.get_info (Mark.remove s)) ); ] "The variable %a.%a cannot be used here, as it is not part of subscope \ %a's results. Maybe you forgot to qualify it as an output?" SubScopeName.format (Mark.remove s) ScopeVar.format (Mark.remove a) SubScopeName.format (Mark.remove s)) | ELocation (ToplevelVar v) -> let v, _ = TopdefName.Map.find (Mark.remove v) ctx.toplevel_vars in Expr.evar v m | EOp { op = Add_dat_dur _; tys } -> Expr.eop (Add_dat_dur ctx.date_rounding) tys m | EOp { op; tys } -> Expr.eop (Operator.translate op) tys m | ( EVar _ | EAbs _ | ELit _ | EExternal _ | EStruct _ | EStructAccess _ | ETuple _ | ETupleAccess _ | EInj _ | EEmptyError | EErrorOnEmpty _ | EArray _ | EIfThenElse _ ) as e -> Expr.map ~f:(translate_expr ctx) (e, m) (** The result of a rule translation is a list of assignment, with variables and expressions. We also return the new translation context available after the assignment to use in later rule translations. The list is actually a continuation yielding a [Dcalc.scope_body_expr] by giving it what should come later in the chain of let-bindings. *) let translate_rule (ctx : 'm ctx) (rule : 'm Scopelang.Ast.rule) ((sigma_name, pos_sigma) : Uid.MarkedString.info) : ('m Ast.expr scope_body_expr Bindlib.box -> 'm Ast.expr scope_body_expr Bindlib.box) * 'm ctx = match rule with | Definition ((ScopelangScopeVar a, var_def_pos), tau, a_io, e) -> let pos_mark, pos_mark_as = pos_mark_mk e in let a_name = ScopeVar.get_info (Mark.remove a) in let a_var = Var.make (Mark.remove a_name) in let new_e = translate_expr ctx e in let a_expr = Expr.make_var a_var (pos_mark var_def_pos) in let is_func = match Mark.remove tau with TArrow _ -> true | _ -> false in let merged_expr = match Mark.remove a_io.io_input with | OnlyInput -> failwith "should not happen" (* scopelang should not contain any definitions of input only variables *) | Reentrant -> merge_defaults ~is_func a_expr new_e | NoInput -> if is_func then new_e else Expr.eerroronempty new_e (pos_mark_as a_name) in let merged_expr = tag_with_log_entry merged_expr (VarDef { log_typ = Mark.remove tau; log_io_output = Mark.remove a_io.io_output; log_io_input = Mark.remove a_io.io_input; }) [sigma_name, pos_sigma; a_name] in ( (fun next -> Bindlib.box_apply2 (fun next merged_expr -> ScopeLet { scope_let_next = next; scope_let_typ = tau; scope_let_expr = merged_expr; scope_let_kind = ScopeVarDefinition; scope_let_pos = Mark.get a; }) (Bindlib.bind_var a_var next) (Expr.Box.lift merged_expr)), { ctx with scope_vars = ScopeVar.Map.add (Mark.remove a) (a_var, Mark.remove tau, a_io) ctx.scope_vars; } ) | Definition ( (SubScopeVar (_subs_name, subs_index, subs_var), var_def_pos), tau, a_io, e ) -> let a_name = Mark.map (fun str -> str ^ "." ^ Mark.remove (ScopeVar.get_info (Mark.remove subs_var))) (SubScopeName.get_info (Mark.remove subs_index)) in let a_var = Var.make (Mark.remove a_name) in let new_e = tag_with_log_entry (translate_expr ctx e) (VarDef { log_typ = Mark.remove tau; log_io_output = false; log_io_input = Mark.remove a_io.Desugared.Ast.io_input; }) [sigma_name, pos_sigma; a_name] in let is_func = match Mark.remove tau with TArrow _ -> true | _ -> false in let thunked_or_nonempty_new_e = thunk_scope_arg ~is_func a_io.Desugared.Ast.io_input new_e in ( (fun next -> Bindlib.box_apply2 (fun next thunked_or_nonempty_new_e -> ScopeLet { scope_let_next = next; scope_let_pos = Mark.get a_name; scope_let_typ = (match Mark.remove a_io.io_input with | NoInput -> failwith "should not happen" | OnlyInput -> tau | Reentrant -> if is_func then tau else TArrow ([TLit TUnit, var_def_pos], tau), var_def_pos); scope_let_expr = thunked_or_nonempty_new_e; scope_let_kind = SubScopeVarDefinition; }) (Bindlib.bind_var a_var next) (Expr.Box.lift thunked_or_nonempty_new_e)), { ctx with subscope_vars = SubScopeName.Map.update (Mark.remove subs_index) (fun map -> match map with | Some map -> Some (ScopeVar.Map.add (Mark.remove subs_var) (a_var, Mark.remove tau, a_io) map) | None -> Some (ScopeVar.Map.singleton (Mark.remove subs_var) (a_var, Mark.remove tau, a_io))) ctx.subscope_vars; } ) | Definition ((ToplevelVar _, _), _, _, _) -> assert false (* A global variable can't be defined locally. The [Definition] constructor could be made more specific to avoid this case, but the added complexity didn't seem worth it *) | Call (subname, subindex, m) -> let subscope_sig = ScopeName.Map.find subname ctx.scopes_parameters in let all_subscope_vars = subscope_sig.scope_sig_local_vars in let all_subscope_input_vars = List.filter (fun var_ctx -> match Mark.remove var_ctx.scope_var_io.Desugared.Ast.io_input with | NoInput -> false | _ -> true) all_subscope_vars in let all_subscope_output_vars = List.filter (fun var_ctx -> Mark.remove var_ctx.scope_var_io.Desugared.Ast.io_output) all_subscope_vars in let scope_dcalc_var = subscope_sig.scope_sig_scope_var in let called_scope_input_struct = subscope_sig.scope_sig_input_struct in let called_scope_return_struct = subscope_sig.scope_sig_output_struct in let subscope_vars_defined = try SubScopeName.Map.find subindex ctx.subscope_vars with Not_found -> ScopeVar.Map.empty in let subscope_var_not_yet_defined subvar = not (ScopeVar.Map.mem subvar subscope_vars_defined) in let pos_call = Mark.get (SubScopeName.get_info subindex) in let subscope_args = List.fold_left (fun acc (subvar : scope_var_ctx) -> let e = if subscope_var_not_yet_defined subvar.scope_var_name then (* This is a redundant check. Normally, all subscope variables should have been defined (even an empty definition, if they're not defined by any rule in the source code) by the translation from desugared to the scope language. *) Expr.empty_thunked_term m else let a_var, _, _ = ScopeVar.Map.find subvar.scope_var_name subscope_vars_defined in Expr.make_var a_var (mark_tany m pos_call) in let field = (ScopeVar.Map.find subvar.scope_var_name subscope_sig.scope_sig_in_fields) .scope_input_name in StructField.Map.add field e acc) StructField.Map.empty all_subscope_input_vars in let subscope_struct_arg = Expr.estruct called_scope_input_struct subscope_args (mark_tany m pos_call) in let all_subscope_output_vars_dcalc = List.map (fun (subvar : scope_var_ctx) -> let sub_dcalc_var = Var.make (Mark.remove (SubScopeName.get_info subindex) ^ "." ^ Mark.remove (ScopeVar.get_info subvar.scope_var_name)) in subvar, sub_dcalc_var) all_subscope_output_vars in let subscope_func = tag_with_log_entry (Expr.make_var scope_dcalc_var (mark_tany m pos_call)) BeginCall [ sigma_name, pos_sigma; SubScopeName.get_info subindex; ScopeName.get_info subname; ] in let call_expr = tag_with_log_entry (Expr.eapp subscope_func [subscope_struct_arg] (mark_tany m pos_call)) EndCall [ sigma_name, pos_sigma; SubScopeName.get_info subindex; ScopeName.get_info subname; ] in let result_tuple_var = Var.make "result" in let result_tuple_typ = TStruct called_scope_return_struct, pos_sigma in let call_scope_let next = Bindlib.box_apply2 (fun next call_expr -> ScopeLet { scope_let_next = next; scope_let_pos = pos_sigma; scope_let_kind = CallingSubScope; scope_let_typ = result_tuple_typ; scope_let_expr = call_expr; }) (Bindlib.bind_var result_tuple_var next) (Expr.Box.lift call_expr) in let result_bindings_lets next = List.fold_right (fun (var_ctx, v) next -> let field = ScopeVar.Map.find var_ctx.scope_var_name subscope_sig.scope_sig_out_fields in Bindlib.box_apply2 (fun next r -> ScopeLet { scope_let_next = next; scope_let_pos = pos_sigma; scope_let_typ = var_ctx.scope_var_typ, pos_sigma; scope_let_kind = DestructuringSubScopeResults; scope_let_expr = ( EStructAccess { name = called_scope_return_struct; e = r; field }, mark_tany m pos_sigma ); }) (Bindlib.bind_var v next) (Expr.Box.lift (Expr.make_var result_tuple_var (mark_tany m pos_sigma)))) all_subscope_output_vars_dcalc next in ( (fun next -> call_scope_let (result_bindings_lets next)), { ctx with subscope_vars = SubScopeName.Map.add subindex (List.fold_left (fun acc (var_ctx, dvar) -> ScopeVar.Map.add var_ctx.scope_var_name (dvar, var_ctx.scope_var_typ, var_ctx.scope_var_io) acc) ScopeVar.Map.empty all_subscope_output_vars_dcalc) ctx.subscope_vars; } ) | Assertion e -> let new_e = translate_expr ctx e in let scope_let_pos = Expr.pos e in let scope_let_typ = TLit TUnit, scope_let_pos in ( (fun next -> Bindlib.box_apply2 (fun next new_e -> ScopeLet { scope_let_next = next; scope_let_pos; scope_let_typ; scope_let_expr = (* To ensure that we throw an error if the value is not defined, we add an check "ErrorOnEmpty" here. *) Mark.add (Expr.map_ty (fun _ -> scope_let_typ) (Mark.get e)) (EAssert (Mark.copy e (EErrorOnEmpty new_e))); scope_let_kind = Assertion; }) (Bindlib.bind_var (Var.make "_") next) (Expr.Box.lift new_e)), ctx ) let translate_rules (ctx : 'm ctx) (rules : 'm Scopelang.Ast.rule list) ((sigma_name, pos_sigma) : Uid.MarkedString.info) (mark : 'm mark) (scope_sig : 'm scope_sig_ctx) : 'm Ast.expr scope_body_expr Bindlib.box * 'm ctx = let scope_lets, new_ctx = List.fold_left (fun (scope_lets, ctx) rule -> let new_scope_lets, new_ctx = translate_rule ctx rule (sigma_name, pos_sigma) in (fun next -> scope_lets (new_scope_lets next)), new_ctx) ((fun next -> next), ctx) rules in let return_exp = Expr.estruct scope_sig.scope_sig_output_struct (ScopeVar.Map.fold (fun var (dcalc_var, _, io) acc -> if Mark.remove io.Desugared.Ast.io_output then let field = ScopeVar.Map.find var scope_sig.scope_sig_out_fields in StructField.Map.add field (Expr.make_var dcalc_var (mark_tany mark pos_sigma)) acc else acc) new_ctx.scope_vars StructField.Map.empty) (mark_tany mark pos_sigma) in ( scope_lets (Bindlib.box_apply (fun return_exp -> Result return_exp) (Expr.Box.lift return_exp)), new_ctx ) let translate_scope_decl (ctx : 'm ctx) (scope_name : ScopeName.t) (sigma : 'm Scopelang.Ast.scope_decl) : 'm Ast.expr scope_body Bindlib.box * struct_ctx = let sigma_info = ScopeName.get_info sigma.scope_decl_name in let scope_sig = ScopeName.Map.find sigma.scope_decl_name ctx.scopes_parameters in let scope_variables = scope_sig.scope_sig_local_vars in let ctx = { ctx with scope_name = Some scope_name } in let ctx = (* the context must be initialized for fresh variables for all only-input scope variables *) List.fold_left (fun ctx scope_var -> match Mark.remove scope_var.scope_var_io.io_input with | OnlyInput -> let scope_var_name = ScopeVar.get_info scope_var.scope_var_name in let scope_var_dcalc = Var.make (Mark.remove scope_var_name) in { ctx with scope_vars = ScopeVar.Map.add scope_var.scope_var_name ( scope_var_dcalc, scope_var.scope_var_typ, scope_var.scope_var_io ) ctx.scope_vars; } | _ -> ctx) ctx scope_variables in let date_rounding : date_rounding = match List.find_opt (function Desugared.Ast.DateRounding _, _ -> true) sigma.scope_options with | Some (Desugared.Ast.DateRounding Desugared.Ast.Increasing, _) -> RoundUp | Some (DateRounding Decreasing, _) -> RoundDown | None -> AbortOnRound in let ctx = { ctx with date_rounding } in let scope_input_var = scope_sig.scope_sig_input_var in let scope_input_struct_name = scope_sig.scope_sig_input_struct in let scope_return_struct_name = scope_sig.scope_sig_output_struct in let pos_sigma = Mark.get sigma_info in let rules_with_return_expr, ctx = translate_rules ctx sigma.scope_decl_rules sigma_info sigma.scope_mark scope_sig in let scope_variables = List.map (fun var_ctx -> let dcalc_x, _, _ = ScopeVar.Map.find var_ctx.scope_var_name ctx.scope_vars in var_ctx, dcalc_x) scope_variables in (* first we create variables from the fields of the input struct *) let scope_input_variables = List.filter (fun (var_ctx, _) -> match Mark.remove var_ctx.scope_var_io.io_input with | NoInput -> false | _ -> true) scope_variables in let input_var_typ (var_ctx : scope_var_ctx) = match Mark.remove var_ctx.scope_var_io.io_input with | OnlyInput -> var_ctx.scope_var_typ, pos_sigma | Reentrant -> ( match var_ctx.scope_var_typ with | TArrow _ -> var_ctx.scope_var_typ, pos_sigma | _ -> ( TArrow ([TLit TUnit, pos_sigma], (var_ctx.scope_var_typ, pos_sigma)), pos_sigma )) | NoInput -> failwith "should not happen" in let input_destructurings next = List.fold_right (fun (var_ctx, v) next -> let field = (ScopeVar.Map.find var_ctx.scope_var_name scope_sig.scope_sig_in_fields) .scope_input_name in Bindlib.box_apply2 (fun next r -> ScopeLet { scope_let_kind = DestructuringInputStruct; scope_let_next = next; scope_let_pos = pos_sigma; scope_let_typ = input_var_typ var_ctx; scope_let_expr = ( EStructAccess { name = scope_input_struct_name; e = r; field }, mark_tany sigma.scope_mark pos_sigma ); }) (Bindlib.bind_var v next) (Expr.Box.lift (Expr.make_var scope_input_var (mark_tany sigma.scope_mark pos_sigma)))) scope_input_variables next in let field_map = List.fold_left (fun acc (var_ctx, _) -> let var = var_ctx.scope_var_name in let field = (ScopeVar.Map.find var scope_sig.scope_sig_in_fields).scope_input_name in StructField.Map.add field (input_var_typ var_ctx) acc) StructField.Map.empty scope_input_variables in let new_struct_ctx = StructName.Map.singleton scope_input_struct_name field_map in ( Bindlib.box_apply (fun scope_body_expr -> { scope_body_expr; scope_body_input_struct = scope_input_struct_name; scope_body_output_struct = scope_return_struct_name; }) (Bindlib.bind_var scope_input_var (input_destructurings rules_with_return_expr)), new_struct_ctx ) let translate_program (prgm : 'm Scopelang.Ast.program) : 'm Ast.program = let defs_dependencies = Scopelang.Dependency.build_program_dep_graph prgm in Scopelang.Dependency.check_for_cycle_in_defs defs_dependencies; let defs_ordering = Scopelang.Dependency.get_defs_ordering defs_dependencies in let decl_ctx = prgm.program_ctx in let sctx : 'm scope_sigs_ctx = ScopeName.Map.mapi (fun scope_name scope -> let scope_dvar = Var.make (Mark.remove (ScopeName.get_info scope.Scopelang.Ast.scope_decl_name)) in let scope_return = ScopeName.Map.find scope_name decl_ctx.ctx_scopes in let scope_input_var = Var.make (Mark.remove (ScopeName.get_info scope_name) ^ "_in") in let scope_input_struct_name = StructName.fresh (Mark.map (fun s -> s ^ "_in") (ScopeName.get_info scope_name)) in let scope_sig_in_fields = ScopeVar.Map.filter_map (fun dvar (typ, vis) -> match Mark.remove vis.Desugared.Ast.io_input with | NoInput -> None | OnlyInput | Reentrant -> let info = ScopeVar.get_info dvar in let s = Mark.remove info ^ "_in" in Some { scope_input_name = StructField.fresh (s, Mark.get info); scope_input_io = vis.Desugared.Ast.io_input; scope_input_typ = Mark.remove typ; }) scope.scope_sig in { scope_sig_local_vars = List.map (fun (scope_var, (tau, vis)) -> { scope_var_name = scope_var; scope_var_typ = Mark.remove tau; scope_var_io = vis; }) (ScopeVar.Map.bindings scope.scope_sig); scope_sig_scope_var = scope_dvar; scope_sig_input_var = scope_input_var; scope_sig_input_struct = scope_input_struct_name; scope_sig_output_struct = scope_return.out_struct_name; scope_sig_in_fields; scope_sig_out_fields = scope_return.out_struct_fields; }) prgm.Scopelang.Ast.program_scopes in let top_ctx = let toplevel_vars = TopdefName.Map.mapi (fun name (_, ty) -> Var.make (Mark.remove (TopdefName.get_info name)), Mark.remove ty) prgm.Scopelang.Ast.program_topdefs in { structs = decl_ctx.ctx_structs; enums = decl_ctx.ctx_enums; scope_name = None; scopes_parameters = sctx; scope_vars = ScopeVar.Map.empty; subscope_vars = SubScopeName.Map.empty; toplevel_vars; date_rounding = AbortOnRound; } in (* the resulting expression is the list of definitions of all the scopes, ending with the top-level scope. The decl_ctx is filled in left-to-right order, then the chained scopes aggregated from the right. *) let rec translate_defs ctx = function | [] -> Bindlib.box Nil, ctx | def :: next -> let ctx, dvar, def = match def with | Scopelang.Dependency.Topdef gname -> let expr, ty = TopdefName.Map.find gname prgm.program_topdefs in let expr = translate_expr ctx expr in ( ctx, fst (TopdefName.Map.find gname ctx.toplevel_vars), Bindlib.box_apply (fun e -> Topdef (gname, ty, e)) (Expr.Box.lift expr) ) | Scopelang.Dependency.Scope scope_name -> let scope = ScopeName.Map.find scope_name prgm.program_scopes in let scope_body, scope_in_struct = translate_scope_decl ctx scope_name scope in ( { ctx with structs = StructName.Map.union (fun _ _ -> assert false) ctx.structs scope_in_struct; }, (ScopeName.Map.find scope_name sctx).scope_sig_scope_var, Bindlib.box_apply (fun body -> ScopeDef (scope_name, body)) scope_body ) in let scope_next, ctx = translate_defs ctx next in let next_bind = Bindlib.bind_var dvar scope_next in ( Bindlib.box_apply2 (fun item next_bind -> Cons (item, next_bind)) def next_bind, ctx ) in let items, ctx = translate_defs top_ctx defs_ordering in { code_items = Bindlib.unbox items; decl_ctx = { decl_ctx with ctx_structs = ctx.structs }; }