(*  Title:      Pure/Isar/args.ML

    Author:     Markus Wenzel, TU Muenchen

Parsing with implicit value assignment.  Concrete argument syntax of

attributes, methods etc.

*)

signature ARGS =

sig

  type token = OuterLex.token

  type src

  val src: (string * token list) * Position.T -> src

  val dest_src: src -> (string * token list) * Position.T

  val pretty_src: Proof.context -> src -> Pretty.T

  val map_name: (string -> string) -> src -> src

  val morph_values: morphism -> src -> src

  val maxidx_values: src -> int -> int

  val assignable: src -> src

  val closure: src -> src

  val context: Proof.context context_parser

  val theory: theory context_parser

  val $$$ : string -> string parser

  val add: string parser

  val del: string parser

  val colon: string parser

  val query: string parser

  val bang: string parser

  val query_colon: string parser

  val bang_colon: string parser

  val parens: ('a parser) -> 'a parser

  val bracks: ('a parser) -> 'a parser

  val mode: string -> bool context_parser

  val maybe: 'a parser -> 'a option parser

  val name_source: string parser

  val name_source_position: (Symbol_Pos.text * Position.T) parser

  val name: string parser

  val binding: binding parser

  val alt_name: string parser

  val symbol: string parser

  val liberal_name: string parser

  val var: indexname parser

  val internal_text: string parser

  val internal_typ: typ parser

  val internal_term: term parser

  val internal_fact: thm list parser

  val internal_attribute: (morphism -> attribute) parser

  val named_text: (string -> string) -> string parser

  val named_typ: (string -> typ) -> typ parser

  val named_term: (string -> term) -> term parser

  val named_fact: (string -> thm list) -> thm list parser

  val named_attribute: (string -> morphism -> attribute) -> (morphism -> attribute) parser

  val typ_abbrev: typ context_parser

  val typ: typ context_parser

  val term: term context_parser

  val term_abbrev: term context_parser

  val prop: term context_parser

  val type_name: bool -> string context_parser

  val const: bool -> string context_parser

  val const_proper: bool -> string context_parser

  val goal_spec: ((int -> tactic) -> tactic) context_parser

  val parse: token list parser

  val parse1: (string -> bool) -> token list parser

  val attribs: (string -> string) -> src list parser

  val opt_attribs: (string -> string) -> src list parser

  val thm_name: (string -> string) -> string -> (binding * src list) parser

  val opt_thm_name: (string -> string) -> string -> (binding * src list) parser

  val syntax: string -> 'a context_parser -> src -> Context.generic -> 'a * Context.generic

  val context_syntax: string -> 'a context_parser -> src -> Proof.context -> 'a * Proof.context

end;

structure Args: ARGS =

struct

structure T = OuterLex;

structure P = OuterParse;

type token = T.token;

(** datatype src **)

datatype src = Src of (string * token list) * Position.T;

val src = Src;

fun dest_src (Src src) = src;

fun pretty_src ctxt src =

  let

    val prt_thm = Pretty.backquote o Display.pretty_thm ctxt;

    fun prt arg =

      (case T.get_value arg of

        SOME (T.Text s) => Pretty.str (quote s)

      | SOME (T.Typ T) => Syntax.pretty_typ ctxt T

      | SOME (T.Term t) => Syntax.pretty_term ctxt t

      | SOME (T.Fact ths) => Pretty.enclose "(" ")" (Pretty.breaks (map prt_thm ths))

      | _ => Pretty.str (T.unparse arg));

    val (s, args) = #1 (dest_src src);

  in Pretty.block (Pretty.breaks (Pretty.str s :: map prt args)) end;

fun map_name f (Src ((s, args), pos)) = Src ((f s, args), pos);

fun map_args f (Src ((s, args), pos)) = Src ((s, map f args), pos);

(* values *)

fun morph_values phi = map_args (T.map_value

  (fn T.Text s => T.Text s

    | T.Typ T => T.Typ (Morphism.typ phi T)

    | T.Term t => T.Term (Morphism.term phi t)

    | T.Fact ths => T.Fact (Morphism.fact phi ths)

    | T.Attribute att => T.Attribute (Morphism.transform phi att)));

fun maxidx_values (Src ((_, args), _)) = args |> fold (fn arg =>

  (case T.get_value arg of

    SOME (T.Typ T) => Term.maxidx_typ T

  | SOME (T.Term t) => Term.maxidx_term t

  | SOME (T.Fact ths) => fold Thm.maxidx_thm ths

  | _ => I));

val assignable = map_args T.assignable;

val closure = map_args T.closure;

(** argument scanners **)

(* context *)

fun context x = (Scan.state >> Context.proof_of) x;

fun theory x = (Scan.state >> Context.theory_of) x;

(* basic *)

fun token atom = Scan.ahead P.not_eof --| atom;

val ident = token

  (P.short_ident || P.long_ident || P.sym_ident || P.term_var ||

    P.type_ident || P.type_var || P.number);

val string = token (P.string || P.verbatim);

val alt_string = token P.alt_string;

val symbolic = token P.keyword_ident_or_symbolic;

fun $$$ x = (ident >> T.content_of || P.keyword)

  :|-- (fn y => if x = y then Scan.succeed x else Scan.fail);

val named = ident || string;

val add = $$$ "add";

val del = $$$ "del";

val colon = $$$ ":";

val query = $$$ "?";

val bang = $$$ "!";

val query_colon = $$$ "?" ^^ $$$ ":";

val bang_colon = $$$ "!" ^^ $$$ ":";

fun parens scan = $$$ "(" |-- scan --| $$$ ")";

fun bracks scan = $$$ "[" |-- scan --| $$$ "]";

fun mode s = Scan.lift (Scan.optional (parens ($$$ s) >> K true) false);

fun maybe scan = $$$ "_" >> K NONE || scan >> SOME;

val name_source = named >> T.source_of;

val name_source_position = named >> T.source_position_of;

val name = named >> T.content_of;

val binding = P.position name >> Binding.make;

val alt_name = alt_string >> T.content_of;

val symbol = symbolic >> T.content_of;

val liberal_name = symbol || name;

val var = (ident >> T.content_of) :|-- (fn x =>

  (case Lexicon.read_variable x of SOME v => Scan.succeed v | NONE => Scan.fail));

(* values *)

fun value dest = Scan.some (fn arg =>

  (case T.get_value arg of SOME v => (SOME (dest v) handle Match => NONE) | NONE => NONE));

fun evaluate mk eval arg =

  let val x = eval arg in (T.assign (SOME (mk x)) arg; x) end;

val internal_text = value (fn T.Text s => s);

val internal_typ = value (fn T.Typ T => T);

val internal_term = value (fn T.Term t => t);

val internal_fact = value (fn T.Fact ths => ths);

val internal_attribute = value (fn T.Attribute att => att);

fun named_text intern = internal_text || named >> evaluate T.Text (intern o T.content_of);

fun named_typ readT = internal_typ || named >> evaluate T.Typ (readT o T.source_of);

fun named_term read = internal_term || named >> evaluate T.Term (read o T.source_of);

fun named_fact get = internal_fact || named >> evaluate T.Fact (get o T.content_of) ||

  alt_string >> evaluate T.Fact (get o T.source_of);

fun named_attribute att = internal_attribute || named >> evaluate T.Attribute (att o T.content_of);

(* terms and types *)

val typ_abbrev = Scan.peek (named_typ o ProofContext.read_typ_abbrev o Context.proof_of);

val typ = Scan.peek (named_typ o Syntax.read_typ o Context.proof_of);

val term = Scan.peek (named_term o Syntax.read_term o Context.proof_of);

val term_abbrev = Scan.peek (named_term o ProofContext.read_term_abbrev o Context.proof_of);

val prop = Scan.peek (named_term o Syntax.read_prop o Context.proof_of);

(* type and constant names *)

fun type_name strict =

  Scan.peek (fn ctxt => named_typ (ProofContext.read_type_name (Context.proof_of ctxt) strict))

  >> (fn Type (c, _) => c | TFree (a, _) => a | _ => "");

fun const strict =

  Scan.peek (fn ctxt => named_term (ProofContext.read_const (Context.proof_of ctxt) strict))

  >> (fn Const (c, _) => c | Free (x, _) => x | _ => "");

fun const_proper strict =

  Scan.peek (fn ctxt => named_term (ProofContext.read_const_proper (Context.proof_of ctxt) strict))

  >> (fn Const (c, _) => c | _ => "");

(* improper method arguments *)

val from_to =

  P.nat -- ($$$ "-" |-- P.nat) >> (fn (i, j) => fn tac => Seq.INTERVAL tac i j) ||

  P.nat --| $$$ "-" >> (fn i => fn tac => fn st => Seq.INTERVAL tac i (Thm.nprems_of st) st) ||

  P.nat >> (fn i => fn tac => tac i) ||

  $$$ "!" >> K ALLGOALS;

val goal = $$$ "[" |-- P.!!! (from_to --| $$$ "]");

fun goal_spec x = Scan.lift (Scan.optional goal (fn tac => tac 1)) x;

(* arguments within outer syntax *)

fun parse_args is_symid =

  let

    val keyword_symid = token (P.keyword_with is_symid);

    fun atom blk = P.group "argument"

      (ident || keyword_symid || string || alt_string ||

        (if blk then token (P.$$$ ",") else Scan.fail));

    fun args blk x = Scan.optional (args1 blk) [] x

    and args1 blk x =

      ((Scan.repeat1

        (Scan.repeat1 (atom blk) ||

          argsp "(" ")" ||

          argsp "[" "]")) >> flat) x

    and argsp l r x = (token (P.$$$ l) ::: P.!!! (args true @@@ (token (P.$$$ r) >> single))) x;

  in (args, args1) end;

val parse = #1 (parse_args T.ident_or_symbolic) false;

fun parse1 is_symid = #2 (parse_args is_symid) false;

(* attributes *)

fun attribs intern =

  let

    val attrib_name = internal_text || (symbolic || named)

      >> evaluate T.Text (intern o T.content_of);

    val attrib = P.position (attrib_name -- P.!!! parse) >> src;

  in $$$ "[" |-- P.!!! (P.list attrib --| $$$ "]") end;

fun opt_attribs intern = Scan.optional (attribs intern) [];

(* theorem specifications *)

fun thm_name intern s = binding -- opt_attribs intern --| $$$ s;

fun opt_thm_name intern s =

  Scan.optional

    ((binding -- opt_attribs intern || attribs intern >> pair Binding.empty) --| $$$ s)

    (Binding.empty, []);

(** syntax wrapper **)

fun syntax kind scan (Src ((s, args), pos)) st =

  (case Scan.error (Scan.finite' T.stopper (Scan.option scan)) (st, args) of

    (SOME x, (st', [])) => (x, st')

  | (_, (_, args')) =>

      error (kind ^ " " ^ quote s ^ Position.str_of pos ^ ": bad arguments\n  " ^

        space_implode " " (map T.unparse args')));

fun context_syntax kind scan src = apsnd Context.the_proof o syntax kind scan src o Context.Proof;

end;