[@@@warning "-30"] exception TODO of string module I = AST open Region module SMap = Map.Make(String) module O = struct type type_name = string type var_name = string type ast = { types : type_decl list; parameter : typed_var; storage : typed_var; operations : typed_var; declarations : decl list; prev : I.ast; } and typed_var = { name:var_name; ty:type_expr } and type_decl = { name:string; ty:type_expr } and decl = { name:var_name; ty:type_expr; value: expr } and type_expr = Prod of type_expr list | Sum of (type_name * type_expr) list | Record of (type_name * type_expr) list | TypeApp of type_name * (type_expr list) | Function of { args: type_expr list; ret: type_expr } | Ref of type_expr | Unit | Int | TODO and expr = App of { operator: operator; arguments: expr list } | Var of var_name | Constant of constant | Lambda of { parameters: type_expr SMap.t; declarations: decl list; instructions: instr list; result: expr; } and operator = Or | And | Lt | Leq | Gt | Geq | Equal | Neq | Cat | Cons | Add | Sub | Mult | Div | Mod | Neg | Not | Function of string and constant = Unit | Int of Z.t | String of string | Bytes of MBytes.t | False | True and instr = | Assignment of { name: var_name; value: expr } | While of { condition: expr; body: instr list } | ForCollection of { list: expr; key: var_name; value: var_name option; body: instr list } | If of { condition: expr; ifso: instr list; ifnot: instr list } | Match of { expr: expr; cases: (pattern * instr list) list } | DropUnit of expr (* expr returns unit, drop the result. *) | Fail of { expr: expr } and pattern = PVar of var_name | PWild | PInt of Z.t | PBytes of MBytes.t | PString of string | PUnit | PFalse | PTrue | PNone | PSome of pattern | Cons of pattern * pattern | Null | PTuple of pattern list end (* open Sanity: *) let (|>) v f = f v (* pipe f to v *) let (@@) f v = f v (* apply f on v *) let (@.) f g x = f (g x) (* compose *) let map f l = List.rev (List.rev_map f l) (* TODO: check that List.to_seq, List.append and SMap.of_seq are not broken (i.e. check that they are tail-recursive) *) let append_map f l = map f l |> List.flatten let append l1 l2 = List.append l1 l2 let list_to_map l = l |> List.to_seq |> SMap.of_seq let fold_map f a l = let f (acc, l) elem = let acc', elem' = f acc elem in acc', (elem' :: l) in let last_acc, last_l = List.fold_left f (a, []) l in last_acc, List.rev last_l (* Simplify the AST *) let s_nsepseq : ('a,'sep) Utils.nsepseq -> 'a list = fun (first, rest) -> first :: (map snd rest) let s_sepseq : ('a,'sep) Utils.sepseq -> 'a list = function None -> [] | Some nsepseq -> s_nsepseq nsepseq let s_name {value=name; region} : O.var_name = let () = ignore (region) in name let rec s_cartesian {value=sequence; region} : O.type_expr = let () = ignore (region) in Prod (map s_type_expr (s_nsepseq sequence)) and s_sum_type {value=sequence; region} : O.type_expr = let () = ignore (region) in Sum (map s_variant (s_nsepseq sequence)) and s_variant {value=(constr, kwd_of, cartesian); region} = let () = ignore (kwd_of,region) in (s_name constr, s_cartesian cartesian) and s_record_type {value=(kwd_record, field_decls, kwd_end); region} : O.type_expr = let () = ignore (kwd_record,region,kwd_end) in Record (map s_field_decl (s_nsepseq field_decls)) and s_field_decl {value=(var, colon, type_expr); region} = let () = ignore (colon,region) in (s_name var, s_type_expr type_expr) and s_type_app {value=(type_name,type_tuple); region} : O.type_expr = let () = ignore (region) in TypeApp (s_name type_name, s_type_tuple type_tuple) and s_type_tuple ({value=(lpar, sequence, rpar); region} : (I.type_name, I.comma) Utils.nsepseq I.par) : O.type_expr list = let () = ignore (lpar,rpar,region) in (* TODO: the grammar should allow any type expr, not just type_name in the tuple elements *) map s_type_expr (map (fun a -> I.TAlias a) (s_nsepseq sequence)) and s_par_type {value=(lpar, type_expr, rpar); region} : O.type_expr = let () = ignore (lpar,rpar,region) in s_type_expr type_expr and s_type_alias name : O.type_expr = let () = ignore () in TypeApp (s_name name, []) and s_type_expr : I.type_expr -> O.type_expr = function Prod cartesian -> s_cartesian cartesian | Sum sum_type -> s_sum_type sum_type | Record record_type -> s_record_type record_type | TypeApp type_app -> s_type_app type_app | ParType par_type -> s_par_type par_type | TAlias type_alias -> s_type_alias type_alias let s_type_decl I.{value={kwd_type;name;kwd_is;type_expr;terminator}; region} : O.type_decl = let () = ignore (kwd_type,kwd_is,terminator,region) in O.{ name = s_name name; ty = s_type_expr type_expr } let s_parameter_decl I.{value={kwd_parameter;name;colon;param_type;terminator};region} : O.typed_var = let () = ignore (kwd_parameter,colon,terminator,region) in O.{ name = s_name name; ty = s_type_expr param_type } let s_storage_decl I.{value={kwd_storage; store_type; terminator}; region} : O.typed_var = let () = ignore (kwd_storage,terminator,region) in O.{ name = "storage"; ty = s_type_expr store_type } let s_operations_decl I.{value={kwd_operations;op_type;terminator}; region} : O.typed_var = let () = ignore (kwd_operations,terminator,region) in O.{ name = "operations"; ty = s_type_expr op_type } let rec bin l operator r = O.App { operator; arguments = [s_expr l; s_expr r] } and una operator v = O.App { operator; arguments = [s_expr v] } and s_expr : I.expr -> O.expr = function Or {value=(l, bool_or, r); region} -> let () = ignore (region, bool_or) in bin l Or r | And {value=(l, bool_and, r); region} -> let () = ignore (region,bool_and) in bin l And r | Lt {value=(l, lt, r); region} -> let () = ignore (region, lt) in bin l Lt r | Leq {value=(l, leq, r); region} -> let () = ignore (region, leq) in bin l Leq r | Gt {value=(l, gt, r); region} -> let () = ignore (region, gt) in bin l Gt r | Geq {value=(l, geq, r); region} -> let () = ignore (region, geq) in bin l Geq r | Equal {value=(l, equal, r); region} -> let () = ignore (region, equal) in bin l Equal r | Neq {value=(l, neq, r); region} -> let () = ignore (region, neq) in bin l Neq r | Cat {value=(l, cat, r); region} -> let () = ignore (region, cat) in bin l Cat r | Cons {value=(l, cons, r); region} -> let () = ignore (region, cons) in bin l Cons r | Add {value=(l, plus, r); region} -> let () = ignore (region, plus) in bin l Add r | Sub {value=(l, minus, r); region} -> let () = ignore (region, minus) in bin l Sub r | Mult {value=(l, times, r); region} -> let () = ignore (region, times) in bin l Mult r | Div {value=(l, slash, r); region} -> let () = ignore (region, slash) in bin l Div r | Mod {value=(l, kwd_mod, r); region} -> let () = ignore (region, kwd_mod) in bin l Mod r | Neg {value=(minus, expr); region} -> let () = ignore (region, minus) in una Neg expr | Not {value=(kwd_not, expr); region} -> let () = ignore (region, kwd_not) in una Not expr | Int {value=(lexeme, z); region} -> let () = ignore (region, lexeme) in Constant (Int z) | Var {value=lexeme; region} -> let () = ignore (region) in Var lexeme | String {value=s; region} -> let () = ignore (region) in Constant (String s) | Bytes {value=(lexeme, mbytes); region} -> let () = ignore (region, lexeme) in Constant (Bytes mbytes) | False c_False -> let () = ignore (c_False) in Constant (False) | True c_True -> let () = ignore (c_True) in Constant (True) | Unit c_Unit -> let () = ignore (c_Unit) in Constant (Unit) | Tuple tuple -> let _todo = tuple in raise (TODO "simplify tuple") | List {value=(lbrkt,lst,rbrkt); region} -> let () = ignore (lbrkt,rbrkt,region) in let _todo = lst in raise (TODO "simplify (expr,comma) list") | EmptyList empty_list -> let _todo = empty_list in raise (TODO "simplify (lbracket,rbracket,colon,type_expr) par") | Set set -> let _todo = set in raise (TODO "simplify (expr, comma) nsepseq braces") | EmptySet empty_set -> let _todo = empty_set in raise (TODO "simplify empty_set") | NoneExpr none_expr -> let _todo = none_expr in raise (TODO "simplify (c_None,colon,type_expr) par") | FunCall fun_call -> let _todo = fun_call in raise (TODO "simplify FunCall") | ConstrApp constr_app -> let _todo = constr_app in raise (TODO "simplify ConstrApp") | SomeApp {value=(c_Some, arguments); region} -> let _todo = arguments in let () = ignore (region,c_Some) in raise (TODO "simplify SomeApp") | MapLookUp {value=map_lookup; region} -> let _todo = map_lookup in let () = ignore (region) in raise (TODO "simplify MapLookUp") | ParExpr {value=(lpar,expr,rpar); region} -> let () = ignore (lpar,rpar,region) in s_expr expr let s_case : I.case -> O.pattern * (O.instr list) = function | _ -> raise (TODO "simplify pattern matching cases") let s_const_decl I.{value={kwd_const;name;colon;vtype;equal;init;terminator}; region} : O.decl = let () = ignore (kwd_const,colon,equal,terminator,region) in O.{ name = s_name name; ty = s_type_expr vtype; value = s_expr init } let s_param_const {value=(kwd_const,variable,colon,type_expr); region} : string * O.type_expr = let () = ignore (kwd_const,colon,region) in s_name variable, s_type_expr type_expr let s_param_var {value=(kwd_var,variable,colon,type_expr); region} : string * O.type_expr = let () = ignore (kwd_var,colon,region) in s_name variable, s_type_expr type_expr let s_param_decl : I.param_decl -> string * O.type_expr = function ParamConst p -> s_param_const p | ParamVar p -> s_param_var p let s_parameters ({value=(lpar,param_decl,rpar);region} : I.parameters) : (string * O.type_expr) list = let () = ignore (lpar,rpar,region) in let l = (s_nsepseq param_decl) in map s_param_decl l let rec s_var_decl I.{value={kwd_var;name;colon;vtype;ass;init;terminator}; region} : O.decl = let () = ignore (kwd_var,colon,ass,terminator,region) in O.{ name = s_name name; ty = s_type_expr vtype; value = s_expr init } and s_local_decl : I.local_decl -> O.decl = function LocalLam decl -> s_lambda_decl decl | LocalConst decl -> s_const_decl decl | LocalVar decl -> s_var_decl decl and s_instructions ({value=sequence; region} : I.instructions) : O.instr list = let () = ignore (region) in append_map s_instruction (s_nsepseq sequence) and s_instruction : I.instruction -> O.instr list = function Single instr -> s_single_instr instr | Block block -> (s_block block) and s_conditional I.{kwd_if;test;kwd_then;ifso;kwd_else;ifnot} : O.instr = let () = ignore (kwd_if,kwd_then,kwd_else) in If { condition = s_expr test; ifso = s_instruction ifso; ifnot = s_instruction ifnot } and s_match_instr I.{kwd_match;expr;kwd_with;lead_vbar;cases;kwd_end} : O.instr = let {value=cases;region} = cases in let () = ignore (kwd_match,kwd_with,lead_vbar,kwd_end,region) in Match { expr = s_expr expr; cases = map s_case (s_nsepseq cases) } and s_ass_instr {value=(variable,ass,expr); region} : O.instr = let () = ignore (ass,region) in Assignment { name = s_name variable; value = s_expr expr } and s_while_loop {value=(kwd_while, expr, block); region} : O.instr list = let () = ignore (kwd_while,region) in [While {condition = s_expr expr; body = s_block block}] and s_for_loop : I.for_loop -> O.instr list = function ForInt for_int -> s_for_int for_int | ForCollect for_collect -> s_for_collect for_collect and s_for_int ({value={kwd_for;ass;down;kwd_to;bound;step;block}; region} : I.for_int reg) : O.instr list = let {value=(variable,ass_kwd,expr);region = ass_region} = ass in let () = ignore (kwd_for,ass_region,ass_kwd,kwd_to,region) in let name = s_name variable in let condition, operator = match down with Some kwd_down -> ignore kwd_down; O.Gt, O.Sub | None -> O.Lt, O.Add in let step = s_step step in [ Assignment { name; value = s_expr expr }; (* TODO: lift the declaration of the variable *) While { condition = App { operator = condition; arguments = [Var name; s_expr bound] }; body = append (s_block block) [O.Assignment { name; value = App { operator; arguments = [Var name; step]}}] } ] and s_for_collect ({value={kwd_for;var;bind_to;kwd_in;expr;block}; _} : I.for_collect reg) : O.instr list = let () = ignore (kwd_for,kwd_in) in [ O.ForCollection { list = s_expr expr; key = s_name var; value = s_bind_to bind_to; body = s_block block } ] and s_step : (I.kwd_step * I.expr) option -> O.expr = function Some (kwd_step, expr) -> let () = ignore (kwd_step) in s_expr expr | None -> Constant (Int (Z.of_int 1)) and s_bind_to : (I.arrow * I.variable) option -> O.var_name option = function Some (arrow, variable) -> let () = ignore (arrow) in Some (s_name variable) | None -> None and s_loop : I.loop -> O.instr list = function While while_loop -> s_while_loop while_loop | For for_loop -> s_for_loop for_loop and s_fun_call {value=(fun_name, arguments); region} : O.expr = let () = ignore (region) in App { operator = Function (s_name fun_name); arguments = s_arguments arguments } and s_arguments {value=(lpar, sequence, rpar); region} = let () = ignore (lpar,rpar,region) in map s_expr (s_nsepseq sequence); and s_fail ((kwd_fail, expr) : (I.kwd_fail * I.expr)) : O.instr = let () = ignore (kwd_fail) in Fail { expr = s_expr expr } and s_single_instr : I.single_instr -> O.instr list = function Cond {value; _} -> [s_conditional value] | Match {value; _} -> [s_match_instr value] | Ass instr -> [s_ass_instr instr] | Loop loop -> s_loop loop | ProcCall fun_call -> [DropUnit (s_fun_call fun_call)] | Null kwd_null -> let () = ignore (kwd_null) in [] | Fail {value; _} -> [s_fail value] and s_block I.{value={opening;instr;terminator;close}; _} : O.instr list = let () = ignore (opening,terminator,close) in s_instructions instr and s_fun_decl I.{value={kwd_function;name;param;colon;ret_type;kwd_is;local_decls;block;kwd_with;return;terminator}; region} : O.decl = let () = ignore (kwd_function,colon,kwd_is,kwd_with,terminator,region) in O.{ name = s_name name; ty = Function { args = map snd (s_parameters param); ret = s_type_expr ret_type }; value = Lambda { parameters = s_parameters param |> list_to_map; declarations = map s_local_decl local_decls; instructions = s_block block; result = s_expr return } } and s_proc_decl I.{value={kwd_procedure;name;param;kwd_is;local_decls;block;terminator}; region} = let () = ignore (kwd_procedure,kwd_is,terminator,region) in O.{ name = s_name name; ty = Function { args = map snd (s_parameters param); ret = Unit }; value = Lambda { parameters = s_parameters param |> list_to_map; declarations = map s_local_decl local_decls; instructions = s_block block; result = O.Constant O.Unit } } and s_lambda_decl : I.lambda_decl -> O.decl = function FunDecl fun_decl -> s_fun_decl fun_decl | ProcDecl proc_decl -> s_proc_decl proc_decl let s_main_block (block: I.block reg) : O.decl = O.{ name = "main"; ty = Function { args = []; ret = Unit }; value = Lambda { parameters = SMap.empty; declarations = []; instructions = s_block block; result = O.Constant O.Unit } } let s_ast (ast : I.ast) : O.ast = let I.{types;constants;parameter;storage;operations;lambdas;block;eof} = ast in let () = ignore (eof) in O.{ types = map s_type_decl types; parameter = s_parameter_decl parameter; storage = s_storage_decl storage; operations = s_operations_decl operations; declarations = List.flatten [(map s_const_decl constants); (map s_lambda_decl lambdas); [s_main_block block]]; prev = ast } (* let s_token region lexeme = *) (* printf "%s: %s\n"(compact region) lexeme *) (* and s_var {region; value=lexeme} = *) (* printf "%s: Ident \"%s\"\n" (compact region) lexeme *) (* and s_constr {region; value=lexeme} = *) (* printf "%s: Constr \"%s\"\n" *) (* (compact region) lexeme *) (* and s_string {region; value=lexeme} = *) (* printf "%s: String \"%s\"\n" *) (* (compact region) lexeme *) (* and s_bytes {region; value = lexeme, abstract} = *) (* printf "%s: Bytes (\"%s\", \"0x%s\")\n" *) (* (compact region) lexeme *) (* (MBytes.to_hex abstract |> Hex.to_string) *) (* and s_int {region; value = lexeme, abstract} = *) (* printf "%s: Int (\"%s\", %s)\n" *) (* (compact region) lexeme *) (* (Z.to_string abstract) *) (* and s_parameters {value=node; _} = *) (* let lpar, sequence, rpar = node in *) (* s_token lpar "("; *) (* s_nsepseq ";" s_param_decl sequence; *) (* s_token rpar ")" *) (* and s_param_decl = function *) (* ParamConst param_const -> s_param_const param_const *) (* | ParamVar param_var -> s_param_var param_var *) (* and s_region_cases {value=sequence; _} = *) (* s_nsepseq "|" s_case sequence *) (* and s_case {value=node; _} = *) (* let pattern, arrow, instruction = node in *) (* s_pattern pattern; *) (* s_token arrow "->"; *) (* s_instruction instruction *) (* and s_expr = function *) (* Or {value = expr1, bool_or, expr2; _} -> *) (* s_expr expr1; s_token bool_or "||"; s_expr expr2 *) (* | And {value = expr1, bool_and, expr2; _} -> *) (* s_expr expr1; s_token bool_and "&&"; s_expr expr2 *) (* | Lt {value = expr1, lt, expr2; _} -> *) (* s_expr expr1; s_token lt "<"; s_expr expr2 *) (* | Leq {value = expr1, leq, expr2; _} -> *) (* s_expr expr1; s_token leq "<="; s_expr expr2 *) (* | Gt {value = expr1, gt, expr2; _} -> *) (* s_expr expr1; s_token gt ">"; s_expr expr2 *) (* | Geq {value = expr1, geq, expr2; _} -> *) (* s_expr expr1; s_token geq ">="; s_expr expr2 *) (* | Equal {value = expr1, equal, expr2; _} -> *) (* s_expr expr1; s_token equal "="; s_expr expr2 *) (* | Neq {value = expr1, neq, expr2; _} -> *) (* s_expr expr1; s_token neq "=/="; s_expr expr2 *) (* | Cat {value = expr1, cat, expr2; _} -> *) (* s_expr expr1; s_token cat "^"; s_expr expr2 *) (* | Cons {value = expr1, cons, expr2; _} -> *) (* s_expr expr1; s_token cons "<:"; s_expr expr2 *) (* | Add {value = expr1, add, expr2; _} -> *) (* s_expr expr1; s_token add "+"; s_expr expr2 *) (* | Sub {value = expr1, sub, expr2; _} -> *) (* s_expr expr1; s_token sub "-"; s_expr expr2 *) (* | Mult {value = expr1, mult, expr2; _} -> *) (* s_expr expr1; s_token mult "*"; s_expr expr2 *) (* | Div {value = expr1, div, expr2; _} -> *) (* s_expr expr1; s_token div "/"; s_expr expr2 *) (* | Mod {value = expr1, kwd_mod, expr2; _} -> *) (* s_expr expr1; s_token kwd_mod "mod"; s_expr expr2 *) (* | Neg {value = minus, expr; _} -> *) (* s_token minus "-"; s_expr expr *) (* | Not {value = kwd_not, expr; _} -> *) (* s_token kwd_not "not"; s_expr expr *) (* | Int i -> s_int i *) (* | Var var -> s_var var *) (* | String s -> s_string s *) (* | Bytes b -> s_bytes b *) (* | False region -> s_token region "False" *) (* | True region -> s_token region "True" *) (* | Unit region -> s_token region "Unit" *) (* | Tuple tuple -> s_tuple tuple *) (* | List list -> s_list list *) (* | EmptyList elist -> s_empty_list elist *) (* | Set set -> s_set set *) (* | EmptySet eset -> s_empty_set eset *) (* | NoneExpr nexpr -> s_none_expr nexpr *) (* | FunCall fun_call -> s_fun_call fun_call *) (* | ConstrApp capp -> s_constr_app capp *) (* | SomeApp sapp -> s_some_app sapp *) (* | MapLookUp lookup -> s_map_lookup lookup *) (* | ParExpr pexpr -> s_par_expr pexpr *) (* and s_list {value=node; _} = *) (* let lbra, sequence, rbra = node in *) (* s_token lbra "["; *) (* s_nsepseq "," s_expr sequence; *) (* s_token rbra "]" *) (* and s_empty_list {value=node; _} = *) (* let lpar, (lbracket, rbracket, colon, type_expr), rpar = node in *) (* s_token lpar "("; *) (* s_token lbracket "["; *) (* s_token rbracket "]"; *) (* s_token colon ":"; *) (* s_type_expr type_expr; *) (* s_token rpar ")" *) (* and s_set {value=node; _} = *) (* let lbrace, sequence, rbrace = node in *) (* s_token lbrace "{"; *) (* s_nsepseq "," s_expr sequence; *) (* s_token rbrace "}" *) (* and s_empty_set {value=node; _} = *) (* let lpar, (lbrace, rbrace, colon, type_expr), rpar = node in *) (* s_token lpar "("; *) (* s_token lbrace "{"; *) (* s_token rbrace "}"; *) (* s_token colon ":"; *) (* s_type_expr type_expr; *) (* s_token rpar ")" *) (* and s_none_expr {value=node; _} = *) (* let lpar, (c_None, colon, type_expr), rpar = node in *) (* s_token lpar "("; *) (* s_token c_None "None"; *) (* s_token colon ":"; *) (* s_type_expr type_expr; *) (* s_token rpar ")" *) (* and s_constr_app {value=node; _} = *) (* let constr, arguments = node in *) (* s_constr constr; *) (* s_tuple arguments *) (* and s_some_app {value=node; _} = *) (* let c_Some, arguments = node in *) (* s_token c_Some "Some"; *) (* s_tuple arguments *) (* and s_map_lookup {value=node; _} = *) (* let {value = lbracket, expr, rbracket; _} = node.index in *) (* s_var node.map_name; *) (* s_token node.selector "."; *) (* s_token lbracket "["; *) (* s_expr expr; *) (* s_token rbracket "]" *) (* and s_par_expr {value=node; _} = *) (* let lpar, expr, rpar = node in *) (* s_token lpar "("; *) (* s_expr expr; *) (* s_token rpar ")" *) (* and s_pattern {value=sequence; _} = *) (* s_nsepseq "<:" s_core_pattern sequence *) (* and s_core_pattern = function *) (* PVar var -> s_var var *) (* | PWild wild -> s_token wild "_" *) (* | PInt i -> s_int i *) (* | PBytes b -> s_bytes b *) (* | PString s -> s_string s *) (* | PUnit region -> s_token region "Unit" *) (* | PFalse region -> s_token region "False" *) (* | PTrue region -> s_token region "True" *) (* | PNone region -> s_token region "None" *) (* | PSome psome -> s_psome psome *) (* | PList pattern -> s_list_pattern pattern *) (* | PTuple ptuple -> s_ptuple ptuple *) (* and s_psome {value=node; _} = *) (* let c_Some, patterns = node in *) (* s_token c_Some "Some"; *) (* s_patterns patterns *) (* and s_patterns {value=node; _} = *) (* let lpar, core_pattern, rpar = node in *) (* s_token lpar "("; *) (* s_core_pattern core_pattern; *) (* s_token rpar ")" *) (* and s_list_pattern = function *) (* Sugar sugar -> s_sugar sugar *) (* | Raw raw -> s_raw raw *) (* and s_sugar {value=node; _} = *) (* let lbracket, sequence, rbracket = node in *) (* s_token lbracket "["; *) (* s_sepseq "," s_core_pattern sequence; *) (* s_token rbracket "]" *) (* and s_raw {value=node; _} = *) (* let lpar, (core_pattern, cons, pattern), rpar = node in *) (* s_token lpar "("; *) (* s_core_pattern core_pattern; *) (* s_token cons "<:"; *) (* s_pattern pattern; *) (* s_token rpar ")" *) (* and s_ptuple {value=node; _} = *) (* let lpar, sequence, rpar = node in *) (* s_token lpar "("; *) (* s_nsepseq "," s_core_pattern sequence; *) (* s_token rpar ")" *) (* and s_terminator = function *) (* Some semi -> s_token semi ";" *) (* | None -> () *)