Theory C_Command

(******************************************************************************
 * Isabelle/C
 *
 * Copyright (c) 2018-2019 Université Paris-Saclay, Univ. Paris-Sud, France
 *
 * All rights reserved.
 * Author:     Frédéric Tuong, Burkhart Wolff, Université Paris-Saclay 
 *
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 * modification, are permitted provided that the following conditions are
 * met:
 *
 *     * Redistributions of source code must retain the above copyright
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 *       copyright notice, this list of conditions and the following
 *       disclaimer in the documentation and/or other materials provided
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section ‹Interface: Inner and Outer Commands›

theory C_Command
  imports C_Eval
  keywords "C" :: thy_decl % "ML"
       and "C_file" :: thy_load % "ML"
       and "C_export_boot" :: thy_decl % "ML"
       and "C_export_file" :: thy_decl
       and "C_prf" :: prf_decl % "proof"  (* FIXME % "ML" ?? *)
       and "C_val" :: diag % "ML"
begin

subsection ‹Parsing Entry-Point: Error and Acceptance Cases›

ML ― ‹🗏‹~~/src/Pure/Tools/ghc.ML›
(*  Author:     Frédéric Tuong, Université Paris-Saclay
    Analogous to:
(*  Title:      Pure/Tools/ghc.ML
    Author:     Makarius

Support for GHC: Glasgow Haskell Compiler.
*)*)
structure C_Serialize =
struct

(** string literals **)

fun print_codepoint c =
  (case c of
    10 => "\\n"
  | 9 => "\\t"
  | 11 => "\\v"
  | 8 => "\\b"
  | 13 => "\\r"
  | 12 => "\\f"
  | 7 => "\\a"
  | 27 => "\\e"
  | 92 => "\\\\"
  | 63 => "\\?"
  | 39 => "\\'"
  | 34 => "\\\""
  | c =>
      if c >= 32 andalso c < 127 then chr c
      else error "Not yet implemented");

fun print_symbol sym =
  (case Symbol.decode sym of
    Symbol.Char s => print_codepoint (ord s)
  | Symbol.UTF8 s => UTF8.decode_permissive s |> map print_codepoint |> implode
  | Symbol.Sym s => "\\092<" ^ s ^ ">"
  | Symbol.Control s => "\\092<^" ^ s ^ ">"
  | _ => translate_string (print_codepoint o ord) sym);

val print_string = quote o implode o map print_symbol o Symbol.explode;
end

ML ― ‹analogous to 🗏‹~~/src/Pure/Tools/generated_files.ML›
(*  Author:     Frédéric Tuong, Université Paris-Saclay
    Analogous to:
(*  Title:      Pure/Tools/generated_files.ML
    Author:     Makarius

Generated source files for other languages: with antiquotations, without Isabelle symbols.
*)*)
structure C_Generated_Files =
struct

val c_dir = "C";
val c_ext = "c";
val c_make_comment = enclose "/*" "*/";

(** context data **)

(* file types *)

fun get_file_type ext =
  if ext = "" then error "Bad file extension"
  else if c_ext = ext then ()
  else error ("Unknown file type for extension " ^ quote ext);



(** Isar commands **)

(* generate_file *)

fun generate_file (binding, src_content) lthy =
  let
    val (path, pos) = Path.dest_binding binding;
    val () =
      get_file_type (#2 (Path.split_ext path))
        handle ERROR msg => error (msg ^ Position.here pos);
    val header = c_make_comment " generated by Isabelle ";
    val content = header ^ "\n" ^ src_content;
  in lthy |> (Local_Theory.background_theory o Generated_Files.add_files) (binding,  Bytes.string content) end;



(** concrete file types **)

val _ =
  Theory.setup
    (Generated_Files.file_type bindingC
      {ext = c_ext,
       make_comment = c_make_comment,
       make_string = C_Serialize.print_string});
end

ML ― ‹theoryIsabelle_C.C_Eval signature C_MODULE =
 sig
    structure Data_Accept    : GENERIC_DATA
    structure Data_In_Env    : GENERIC_DATA
    structure Data_In_Source : GENERIC_DATA
    structure Data_Term      : GENERIC_DATA

    structure C_Term:
      sig
        val key0_default: string
        val key0_expression: string
        val key0_external_declaration: string
        val key0_statement: string
        val key0_translation_unit: string
        val key_default: Input.source
        val key_expression: Input.source
        val key_external_declaration: Input.source
        val key_statement: Input.source
        val key_translation_unit: Input.source
        val map_default: (C_Grammar_Rule.ast_generic -> C_Env.env_lang -> local_theory -> term) -> theory -> theory
        val map_expression: (C_Grammar_Rule_Lib.CExpr -> C_Env.env_lang -> local_theory -> term) -> theory -> theory
        val map_external_declaration:
           (C_Grammar_Rule_Lib.CExtDecl -> C_Env.env_lang -> local_theory -> term) -> theory -> theory
        val map_statement: (C_Grammar_Rule_Lib.CStat -> C_Env.env_lang -> local_theory -> term) -> theory -> theory
        val map_translation_unit:
           (C_Grammar_Rule_Lib.CTranslUnit -> C_Env.env_lang -> local_theory -> term) -> theory -> theory
        val tok0_expression: string * ('a * 'a -> (C_Grammar.Tokens.svalue, 'a) LALR_Parser_Eval.Token.token)
        val tok0_external_declaration: string * ('a * 'a -> (C_Grammar.Tokens.svalue, 'a) LALR_Parser_Eval.Token.token)
        val tok0_statement: string * ('a * 'a -> (C_Grammar.Tokens.svalue, 'a) LALR_Parser_Eval.Token.token)
        val tok0_translation_unit: string * ('a * 'a -> (C_Grammar.Tokens.svalue, 'a) LALR_Parser_Eval.Token.token)
        val tok_expression: Input.source * ('a * 'a -> (C_Grammar.Tokens.svalue, 'a) LALR_Parser_Eval.Token.token)
        val tok_external_declaration: Input.source * ('a * 'a -> (C_Grammar.Tokens.svalue, 'a) LALR_Parser_Eval.Token.token)
        val tok_statement: Input.source * ('a * 'a -> (C_Grammar.Tokens.svalue, 'a) LALR_Parser_Eval.Token.token)
        val tok_translation_unit: Input.source * ('a * 'a -> (C_Grammar.Tokens.svalue, 'a) LALR_Parser_Eval.Token.token)
        val tokens: (string * ('a * 'a -> (C_Grammar.Tokens.svalue, 'a) LALR_Parser_Eval.Token.token)) list
      end
    structure C_Term':
      sig
        val accept:
           local_theory ->
             (Input.source * (Position.range -> (C_Grammar.Tokens.svalue, Position.T) LALR_Parser_Eval.Token.token)) option ->
               (Input.source -> Context.generic -> (C_Grammar.Tokens.svalue, Position.T) LALR_Parser_Eval.Token.token) *
               (Data_In_Env.T ->
                  'a * (C_Grammar_Rule.ast_generic * 'b * 'c) ->
                    {context: Context.generic, error_lines: 'd, reports_text: 'e} ->
                      term * {context: Context.generic, error_lines: 'd, reports_text: 'e})
        val err:
           C_Env.env_lang ->
             (LALR_Table.state * (C_Grammar_Parser.svalue0 * Position.T * Position.T)) list ->
               Position.T ->
                 {context: Context.generic, error_lines: string list, reports_text: Position.report_text list} ->
                   term * {context: Context.generic, error_lines: string list, reports_text: Position.report_text list}
        val eval_in:
           Input.source ->
             Context.generic ->
               (Context.generic ->
                  C_Env.env_lang) ->
                 (Input.source * (Position.range -> (C_Grammar.Tokens.svalue, Position.T) LALR_Parser_Eval.Token.token)) option
                   -> C_Lex.token list * (C_Env.error_lines -> string list) -> term
        val parse_translation:
           ('a * (Input.source * (Position.range -> (C_Grammar.Tokens.svalue, Position.T) LALR_Parser_Eval.Token.token)) option)
           list
             -> ('a * (Proof.context -> term list -> term)) list
      end

    val accept:
       Data_In_Env.T ->
         'a * (C_Grammar_Rule.ast_generic * 'b * 'c) ->
           {context: Context.generic, error_lines: 'd, reports_text: 'e} ->
             unit * {context: Context.generic, error_lines: 'd, reports_text: 'e}
    val accept0:
       (Context.generic -> C_Grammar_Rule.ast_generic -> Data_In_Env.T -> Context.generic -> 'a) ->
         Data_In_Env.T -> C_Grammar_Rule.ast_generic -> Context.generic -> 'a
    val c_enclose: string -> string -> Input.source -> C_Lex.token list * (string list -> string list)
    val env: Context.generic -> Data_In_Env.T
    val env0: Proof.context -> Data_In_Env.T
    val err:
       C_Env.env_lang ->
         (LALR_Table.state * (C_Grammar_Parser.svalue0 * Position.T * Position.T)) list ->
           Position.T ->
             {context: Context.generic, error_lines: string list, reports_text: Position.report_text list} ->
               unit * {context: Context.generic, error_lines: string list, reports_text: Position.report_text list}
    val err0:
       'a ->
         'b ->
           Position.T ->
             {context: 'c, error_lines: string list, reports_text: 'd} ->
               {context: 'c, error_lines: string list, reports_text: 'd}
    val eval_in: Input.source -> Context.generic option -> C_Lex.token list * (C_Env.error_lines -> string list) -> unit
    val eval_source: Input.source -> unit
    val exec_eval: Input.source -> Context.generic -> Context.generic
    val start: Input.source -> Context.generic -> (C_Grammar.Tokens.svalue, Position.T) LALR_Parser_Eval.Token.token


    (* toplevel command semantics of Isabelle_C *)
    val C: Input.source -> Context.generic -> Context.generic
    val C': C_Env.env_lang option -> Input.source -> Context.generic -> Context.generic
    val C_export_boot: Input.source -> Context.generic -> generic_theory
    val C_export_file: Position.T * 'a -> Proof.context -> Proof.context
    val C_prf: Input.source -> Proof.state -> Proof.state

  end

structure C_Module : C_MODULE =
struct

structure Data_In_Source = Generic_Data
  (type T = Input.source list
   val empty = []
   val merge = K empty)

structure Data_In_Env = Generic_Data
  (type T = C_Env.env_lang
   val empty = C_Env.empty_env_lang
   val merge = K empty)

structure Data_Accept = Generic_Data
  (type T = C_Grammar_Rule.ast_generic -> C_Env.env_lang -> Context.generic -> Context.generic
   fun empty _ _ = I
   val merge = #2)

structure Data_Term = Generic_Data
  (type T = (C_Grammar_Rule.ast_generic -> C_Env.env_lang -> local_theory -> term) Symtab.table
   val empty = Symtab.empty
   val merge = #2)

(* keys for major syntactic categories *)
structure C_Term =
struct
   val key_translation_unit     = translation_unit›
   val key_external_declaration = external_declaration›
   val key_statement            = statement›
   val key_expression           = expression›
   val key_default              = default›

local
   val source_content = Input.source_content #> #1
in
   val key0_translation_unit = source_content key_translation_unit
   val key0_external_declaration = source_content key_external_declaration
   val key0_statement = source_content key_statement
   val key0_expression = source_content key_expression
   val key0_default = source_content key_default
end

   val tok0_translation_unit = (key0_translation_unit, C_Grammar.Tokens.start_translation_unit)
   val tok0_external_declaration = ( key0_external_declaration
                                   , C_Grammar.Tokens.start_external_declaration)
   val tok0_statement = (key0_statement, C_Grammar.Tokens.start_statement)
   val tok0_expression = (key0_expression, C_Grammar.Tokens.start_expression)
   
   val tok_translation_unit = (key_translation_unit, C_Grammar.Tokens.start_translation_unit)
   val tok_external_declaration = ( key_external_declaration
                                  , C_Grammar.Tokens.start_external_declaration)
   val tok_statement = (key_statement, C_Grammar.Tokens.start_statement)
   val tok_expression = (key_expression, C_Grammar.Tokens.start_expression)
   
   val tokens = [ tok0_translation_unit
                , tok0_external_declaration
                , tok0_statement
                , tok0_expression ]
    
local
   fun map_upd0 key v = Context.theory_map (Data_Term.map (Symtab.update (key, v)))
   fun map_upd key start f = map_upd0 key (f o the o start)
in
   val map_translation_unit = map_upd key0_translation_unit C_Grammar_Rule.get_CTranslUnit
   val map_external_declaration = map_upd key0_external_declaration C_Grammar_Rule.get_CExtDecl
   val map_statement = map_upd key0_statement C_Grammar_Rule.get_CStat
   val map_expression = map_upd key0_expression C_Grammar_Rule.get_CExpr
   val map_default = map_upd0 key0_default
end

end

fun env0 ctxt =
  case Config.get ctxt C_Options.starting_env of
    "last" => Data_In_Env.get (Context.Proof ctxt)
  | "empty" => C_Env.empty_env_lang
  | s => error ("Unknown option: " ^ s ^ Position.here (Config.pos_of C_Options.starting_env))

val env = env0 o Context.proof_of

fun start source context =
 Input.range_of source
 |>
  let val s = Config.get (Context.proof_of context) C_Options.starting_rule
  in case AList.lookup (op =) C_Term.tokens s of
       SOME tok => tok
     | NONE => error ("Unknown option: " ^ s
                                         ^ Position.here (Config.pos_of C_Options.starting_rule))
  end

fun err0 _ _ pos =
  C_Env.map_error_lines (cons ("Parser: No matching grammar rule" ^ Position.here pos))

val err = pair () oooo err0

fun accept0 f (env_lang:C_Env.env_lang) ast =
  Data_In_Env.put env_lang
  #> (fn context => f context ast env_lang (Data_Accept.get context ast env_lang context))

fun accept (env_lang:C_Env.env_lang) (_, (ast, _, _)) =
  pair () o C_Env.map_context (accept0 (K (K (K I))) env_lang ast)

val eval_source = C_Context.eval_source env start err accept

fun c_enclose bg en source =
  C_Lex.@@ ( C_Lex.@@ (C_Lex.read bg, C_Lex.read_source source)
           , C_Lex.read en);

structure C_Term' =
struct
val err = pair Term.dummy oooo err0

fun accept ctxt start_rule =
  let 
    val (key, start) =
      case start_rule of NONE => (C_Term.key_default, start)
                       | SOME (key, start_rule) =>
                           (key, fn source => fn _ => start_rule (Input.range_of source))
    val (key, pos) = Input.source_content key
  in
    ( start
    , fn env_lang => fn (_, (ast, _, _)) =>
        C_Env.map_context'
          (accept0
            (fn context =>
              pair oo (case Symtab.lookup (Data_Term.get context) key of
                         NONE => tap (fn _ => warning ("Representation function associated to\
                                                       \ \"" ^ key ^ "\"" ^ Position.here pos
                                                       ^ " not found (returning a dummy term)"))
                                     (fn _ => fn _ => @{term "()"})
                       | SOME f => fn ast => fn env_lang => f ast env_lang ctxt))
            env_lang
            ast))
  end

fun eval_in text context env start_rule =
  let 
    val (start, accept) = accept (Context.proof_of context) start_rule
  in
    C_Context.eval_in (SOME context) env (start text) err accept
  end

fun parse_translation l = l |>
  map
  (apsnd
    (fn start_rule => fn ctxt => fn args =>
      let val msg = (case start_rule of NONE => C_Term.key_default
                                      | SOME (key, _) => key)
                    |> Input.source_content |> #1
          fun err () = raise TERM (msg, args)
      in
       case args of
         [(c as Const (syntax_const‹_constrain›, _)) $ Free (s, _) $ p] =>
          (case Term_Position.decode_position1 p of
            SOME pos =>
            c
            $ let val src = 
                uncurry
                  (Input.source false)
                  let val s0 = Symbol_Pos.explode (s, pos)
                      val s = Symbol_Pos.cartouche_content s0
                  in
                    ( Symbol_Pos.implode s
                    , case s of [] => Position.no_range
                              | (_, pos0) :: _ => Position.range (pos0, s0 |> List.last |> snd))
                  end
              in
              eval_in
                src
                (case Context.get_generic_context () of
                   NONE => Context.Proof ctxt
                 | SOME context => Context.mapping I (K ctxt) context)
                (C_Stack.Data_Lang.get #> (fn NONE => env0 ctxt
                                            | SOME (_, env_lang) => env_lang))
                start_rule
                (c_enclose "" "" src)
              end
            $ p
          | NONE => err ())
       | _ => err ()
      end))
end

fun eval_in text ctxt = C_Context.eval_in ctxt env (start text) err accept

fun exec_eval source =
  Data_In_Source.map (cons source)
  #> ML_Context.exec (fn () => eval_source source)

fun C_prf source =
  Proof.map_context (Context.proof_map (exec_eval source))
  #> Proof.propagate_ml_env

fun C_export_boot source context =
  context
  |> Config.put_generic ML_Env.ML_environment ML_Env.Isabelle
  |> Config.put_generic ML_Env.ML_write_global true
  |> exec_eval source
  |> Config.restore_generic ML_Env.ML_write_global context
  |> Config.restore_generic ML_Env.ML_environment context
  |> Local_Theory.propagate_ml_env

fun C source =
  exec_eval source
  #> Local_Theory.propagate_ml_env 
val _ =  C: Input.source -> Context.generic -> Context.generic 

val C' =
  let
    fun C env_lang src context =
      context
      |> C_Env.empty_env_tree
      |> C_Context.eval_source'
           env_lang
           (fn src => start src context)
           err
           accept
           src
      |> (fn (_, {context, reports_text, error_lines}) => 
         tap (fn _ => case error_lines of [] => () | l => warning (cat_lines (rev l)))
             (C_Stack.Data_Tree.map (curry C_Stack.Data_Tree_Args.merge (reports_text, []))
                                    context))
  in
    fn NONE => (fn src => C (env (Context.the_generic_context ())) src)
     | SOME env_lang => C env_lang
  end
val _ = C' : C_Env.env_lang option -> Input.source -> Context.generic -> Context.generic


fun C_export_file (pos, _) lthy =
  let
    val c_sources = Data_In_Source.get (Context.Proof lthy)
    val binding =
      Path.binding
        ( Path.appends [ Path.basic C_Generated_Files.c_dir
                       , Path.basic (string_of_int (length c_sources))
                       , lthy |> Proof_Context.theory_of |> Context.theory_base_name |> Path.explode
                              |> Path.ext C_Generated_Files.c_ext ]
        , pos)
  in
    lthy
    |> C_Generated_Files.generate_file (binding, rev c_sources |> map (Input.source_content #> #1)
                                                               |> cat_lines)
    |> tap (Proof_Context.theory_of
            #> (fn thy => let val file = Generated_Files.get_file thy binding
                          in Generated_Files.export_file thy file;
                             writeln (Export.message thy Path.current);
                             writeln (prefix "  " (Generated_Files.print_file file))
                          end))
  end
end

subsection ‹Definitions of C11 Directives as C-commands›

subsubsection ‹Initialization›

ML ― ‹analogous to theoryPure structure C_Directive :
 sig
    val setup_define:
          Position.T ->
             (C_Lex.token list -> string * Position.range -> Context.generic 
              -> C_Lex.token list * Context.generic) ->
              (string * Position.range -> Context.generic -> Context.generic) -> theory -> theory
  end =
struct
local
fun directive_update keyword data = C_Context.directive_update keyword (data, K (K (K I)))
fun return f (env_cond, env) = ([], (env_cond, f env))
fun directive_update_define pos f_toks f_antiq =
  directive_update ("define", pos)
    (return
     o
      (fn C_Lex.Define (_, C_Lex.Group1 ([], [tok3]), NONE, C_Lex.Group1 ([], toks)) =>
          let val map_ctxt = 
              case (tok3, toks) of
                (C_Lex.Token ((pos, _), (C_Lex.Ident _, ident)),
                 [C_Lex.Token (_, (C_Lex.Integer (_, C_Lex.Repr_decimal, []), integer))]) =>
                  C_Env.map_context
                    (Context.map_theory
                      (Named_Target.theory_map
                        (Specification.definition_cmd
                          (SOME (Binding.make (ident, pos), NONE, NoSyn))
                          []
                          []
                          (Binding.empty_atts, ident ^ " ≡ " ^ integer)
                          true
                         #> tap (fn ((_, (_, t)), ctxt) =>
                                 Output.information
                                   ("Generating "
                                    ^ Pretty.string_of (Syntax.pretty_term ctxt (Thm.prop_of t))
                                    ^ Position.here
                                        (Position.range_position
                                          ( C_Lex.pos_of tok3
                                          , C_Lex.end_pos_of (List.last toks)))))
                         #> #2)))
              | _ => I
          in 
            fn (env_dir, env_tree) =>
              let val name = C_Lex.content_of tok3
                  val pos = [C_Lex.pos_of tok3]
                  val data = (pos, serial (), (C_Scan.Left (f_toks toks), f_antiq))
              in
                ( Symtab.update (name, data) env_dir
                , env_tree |> C_Context.markup_directive_define
                                false
                                (C_Ast.Left (data, C_Env_Ext.list_lookup env_dir name))
                                pos
                                name
                           |> map_ctxt)
              end
          end
        | C_Lex.Define (_, C_Lex.Group1 ([], [tok3]), SOME (C_Lex.Group1 (_ :: toks_bl, _)), _)
          =>
            tap (fn _ => (* not yet implemented *)
                   warning ("Ignored functional macro directive"
                            ^ Position.here
                                (Position.range_position
                                  (C_Lex.pos_of tok3, C_Lex.end_pos_of (List.last toks_bl)))))
        | _ => I))
in
val setup_define = Context.theory_map o C_Context0.Directives.map ooo directive_update_define

val _ =
  Theory.setup
  (Context.theory_map
    (C_Context0.Directives.map
      (directive_update_define  (K o pair) (K I)
       #>
       directive_update ("undef", )
        (return
         o
          (fn C_Lex.Undef (C_Lex.Group2 (_, _, [tok])) =>
                (fn (env_dir, env_tree) =>
                  let val name = C_Lex.content_of tok
                      val pos1 = [C_Lex.pos_of tok]
                      val data = Symtab.lookup env_dir name
                  in ( (case data of NONE => env_dir | SOME _ => Symtab.delete name env_dir)
                     , C_Context.markup_directive_define true
                                                         (C_Ast.Right (pos1, data))
                                                         pos1
                                                         name
                                                         env_tree)
                  end)
            | _ => I)))))
end
end

subsection ‹Definitions of C Annotation Commands›
subsubsection ‹Library›

ML ― ‹analogous to 🗏‹~~/src/Pure/Isar/toplevel.ML› structure C_Inner_Toplevel =
struct
val theory = Context.map_theory
fun local_theory' target f gthy =
  let
    val (finish, lthy) = Target_Context.switch_named_cmd target gthy;
    val lthy' = lthy
      |> Local_Theory.new_group
      |> f false
      |> Local_Theory.reset_group;
  in finish lthy' end
val generic_theory = I
fun keep'' f = tap (f o Context.proof_of)
end

ML ― ‹analogous to 🗏‹~~/src/Pure/Isar/isar_cmd.ML› structure C_Inner_Isar_Cmd = 
struct


(** theory declarations **)

(* generic setup *)

fun setup0 f_typ f_val src =
 fn NONE =>
    let val setup = "setup"
    in C_Context.expression
        "C_Ast"
        (Input.range_of src)
        setup
        (f_typ "C_Stack.stack_data"
               "C_Stack.stack_data_elem -> C_Env.env_lang -> Context.generic -> Context.generic")
        ("fn context => \
           \let val (stack, env_lang) = C_Stack.Data_Lang.get' context \
           \in " ^ f_val setup "stack" ^ " (stack |> hd) env_lang end context")
        (ML_Lex.read_source src) end
  | SOME rule => 
    let val hook = "hook"
    in C_Context.expression
        "C_Ast"
        (Input.range_of src)
        hook
        (f_typ "C_Stack.stack_data"
               (C_Grammar_Rule.type_reduce rule
                ^ " C_Stack.stack_elem -> C_Env.env_lang -> Context.generic -> Context.generic"))
        ("fn context => \
           \let val (stack, env_lang) = C_Stack.Data_Lang.get' context \
           \in " ^ f_val hook
                         "stack" ^ " "
                       ^ "(stack \
                           \|> hd \
                           \|> C_Stack.map_svalue0 C_Grammar_Rule.reduce" ^ Int.toString rule ^ ")\
                         \env_lang \
           \end \
           \  context")
        (ML_Lex.read_source src)
    end
val setup = setup0 (fn a => fn b => a ^ " -> " ^ b) (fn a => fn b => a ^ " " ^ b)
val setup' = setup0 (K I) K


(* print theorems, terms, types etc. *)

local

fun string_of_term ctxt s =
  let
    val t = Syntax.read_term ctxt s;
    val T = Term.type_of t;
    val ctxt' = Proof_Context.augment t ctxt;
  in
    Pretty.string_of
      (Pretty.block [Pretty.quote (Syntax.pretty_term ctxt' t), Pretty.fbrk,
        Pretty.str "::", Pretty.brk 1, Pretty.quote (Syntax.pretty_typ ctxt' T)])
  end;

fun print_item string_of (modes, arg) ctxt =
  Print_Mode.with_modes modes (fn () => writeln (string_of ctxt arg)) ();

in

val print_term = print_item string_of_term;

end;

end

ML ― ‹analogous to 🗏‹~~/src/Pure/Isar/outer_syntax.ML› signature C_INNER_SYNTAX =
  sig
    val bottom_up: C_Env.env_propagation_ctxt -> C_Env.env_propagation
    val command:  ('a -> C_Env.env_propagation_ctxt) 
                  -> 'a C_Parse.parser 
                  -> string * Position.T * Position.T 
                  -> theory -> theory
    val command': ('a -> C_Env.comment_style -> Context.generic -> Context.generic,
                  ('a -> 'b) * ('b -> C_Env.env_propagation)) C_Scan.either
                  -> 'a C_Parse.parser -> string * Position.T -> theory -> theory
    val command0: ('a -> Context.generic -> Context.generic) 
                  ->  'a C_Parse.parser 
                  -> string * Position.T * Position.T * Position.T 
                  -> theory -> theory
    val command0':('a -> Context.generic -> Context.generic) 
                  -> string 
                  -> 'a C_Parse.parser 
                  -> string * Position.T * Position.T * Position.T 
                  -> theory -> theory
    val command00:('a -> Position.range -> C_Env.comment_style -> Context.generic -> Context.generic,
                   ('a -> Position.range -> 'b) * ('b -> C_Env.env_propagation)) C_Scan.either
                  -> string -> 'a C_Parse.parser -> string * Position.T 
                  -> theory -> theory
    val command00_no_range:
                  (Position.range -> C_Env.comment_style -> Context.generic -> Context.generic,
                   (Position.range -> 'a) * ('a -> C_Env.env_propagation)) C_Scan.either
                  -> string -> string * Position.T -> theory -> theory
(*    val command0_no_range:
       (range -> Context.generic, (range -> 'a) * (('c -> 'b -> 'a) -> C_Env.env_propagation))
       C_Scan.either
         -> string * T -> theory -> theory
*)
    val command2:
       (('a, 'b * (C_Env.env_propagation_ctxt -> C_Env.env_propagation)) C_Scan.either ->
          string -> string * 'c -> 'd -> 'd)
         -> 'b -> string * 'c * 'c -> 'd -> 'd
    val command2':
       (('a, 'b * (C_Env.env_propagation_ctxt -> C_Env.env_propagation)) C_Scan.either ->
          string -> (string -> string) * 'c -> 'd -> 'd)
         -> 'b -> 'c * 'c -> 'd -> 'd
    val command3:
       (('a, 'a * (C_Env.env_propagation_ctxt -> C_Env.env_propagation)) C_Scan.either ->
          string * 'b -> 'c -> 'c)
         -> 'a -> string * 'b * 'b * 'b -> 'c -> 'c
    val command3':
       (('a, 'a * (C_Env.env_propagation_ctxt -> C_Env.env_propagation)) C_Scan.either ->
          (string -> string) * 'b -> 'c -> 'c)
         -> 'a -> 'b * 'b * 'b -> 'c -> 'c
    val command_no_range: C_Env.env_propagation_ctxt 
                          -> string * Position.T * Position.T -> theory -> theory
    val command_no_range':
       (Position.range -> Context.generic -> Context.generic,
       (Position.range -> 'a) * (('b -> 'a) -> C_Env.env_propagation))
       C_Scan.either
         -> string * Position.T -> theory -> theory
    val command_range:
       (Position.range -> C_Env.comment_style -> Context.generic -> Context.generic,
       (Position.range -> 'a) * ('a -> C_Env.env_propagation))
       C_Scan.either
         -> string * Position.T -> theory -> theory
    val command_range':
       (Position.range -> Context.generic -> Context.generic) 
        -> string * Position.T * Position.T * Position.T -> theory -> theory
    val drop1:
       ('a -> 'b, ('c -> 'd) * 'e) C_Scan.either ->
         ('a -> 'f -> 'b, ('c -> 'g -> 'd) * 'e) C_Scan.either
    val drop2:
       ('a -> 'b, ('c -> 'd) * 'e) C_Scan.either ->
         ('a -> 'f -> 'g -> 'b, ('c -> 'h -> 'i -> 'd) * 'e) C_Scan.either
    val local_command':
       string * Position.T * Position.T * Position.T ->
         ((string -> string) -> Token.T list -> 'a * Token.T list) ->
           ('a -> bool -> local_theory -> local_theory) -> theory -> theory
    val local_command'':
       string * Position.T * Position.T * Position.T ->
         (Token.T list -> 'a * Token.T list) ->
           ('a -> bool -> local_theory -> local_theory) -> theory -> theory
    val pref_bot: 'a -> 'a
    val pref_lex: string -> string
    val pref_top: string -> string
  end

structure C_Inner_Syntax : C_INNER_SYNTAX=
struct
val drop1 = fn C_Scan.Left f => C_Scan.Left (K o f)
             | C_Scan.Right (f, dir) => C_Scan.Right (K o f, dir)

val drop2 = fn C_Scan.Left f => C_Scan.Left (K o K o f)
             | C_Scan.Right (f, dir) => C_Scan.Right (K o K o f, dir)

val bottom_up = C_Env.Bottom_up o C_Env.Exec_annotation

(**)

fun pref_lex name = "#" ^ name
val pref_bot = I
fun pref_top name = name ^ "⇓"

(**)

fun command2' cmd f (pos_bot, pos_top) =
  let fun cmd' dir = cmd (C_Scan.Right (f, dir)) Keyword.thy_decl
  in   cmd' bottom_up (pref_bot, pos_bot)
    #> cmd' C_Env.Top_down (pref_top, pos_top)
  end

fun command3' cmd f (pos_lex, pos_bot, pos_top) =
     cmd (C_Scan.Left f) (pref_lex, pos_lex)
  #> command2' (K o cmd) f (pos_bot, pos_top)

fun command2 cmd f (name, pos_bot, pos_top) =
  command2' (fn f => fn kind => fn (name_pref, pos) => cmd f kind (name_pref name, pos))
            f
            (pos_bot, pos_top)

fun command3 cmd f (name, pos_lex, pos_bot, pos_top) =
  command3' (fn f => fn (name_pref, pos) => cmd f (name_pref name, pos))
            f
            (pos_lex, pos_bot, pos_top)

(**)

fun command00 f kind scan name =
  C_Annotation.command'' kind name ""
    (case f of
       C_Scan.Left f =>
        (fn _ =>
          C_Parse.range scan >>
            (fn (src, range) =>
              C_Env.Lexing (range, f src range)))
     | C_Scan.Right (f, dir) =>
         fn ((stack1, (to_delay, stack2)), _) =>
          C_Parse.range scan >>
            (fn (src, range) =>
              C_Env.Parsing ((stack1, stack2), (range, dir (f src range), Symtab.empty, to_delay))))

val _ = command00 : ('a ->
       Position.range ->
         C_Env.comment_style ->
           Context.generic -> Context.generic
     ,
    ('a -> Position.range -> 'b) * ('b -> C_Env.env_propagation))
    C_Scan.either
      ->
      string -> 'a C_Parse.parser -> string * Position.T -> theory -> theory

fun command00_no_range f kind name =
  C_Annotation.command'' kind name ""
    (case f of
       C_Scan.Left f =>
        (fn (_, range) =>
          Scan.succeed () >>
            K (C_Env.Lexing (range, f range)))
     | C_Scan.Right (f, dir) =>
         fn ((stack1, (to_delay, stack2)), range) =>
          Scan.succeed () >>
            K (C_Env.Parsing ((stack1, stack2), (range, dir (f range), Symtab.empty, to_delay))))

(**)

fun command' f = command00 (drop1 f) Keyword.thy_decl

fun command f scan = command2 (fn f => fn kind => command00 f kind scan) (K o f)

fun command_range f = command00_no_range f Keyword.thy_decl

val command_range' = command3 (command_range o drop1)

fun command_no_range' f = command00_no_range (drop1 f) Keyword.thy_decl

fun command_no_range f = command2 command00_no_range (K f)

fun command0 f scan = command3 (fn f => command' (drop1 f) scan) f

fun local_command' (name, pos_lex, pos_bot, pos_top) scan f =
  command3' (fn f => fn (name_pref, pos) =>
              command' (drop1 f)
                       (C_Token.syntax' (Parse.opt_target -- scan name_pref))
                       (name_pref name, pos))
            (fn (target, arg) => C_Inner_Toplevel.local_theory' target (f arg))
            (pos_lex, pos_bot, pos_top)

fun local_command'' spec = local_command' spec o K

val command0_no_range = command_no_range' o drop1

fun command0' f kind scan =
  command3 (fn f => fn (name, pos) => command00 (drop2 f) kind (scan name) (name, pos)) f

fun command0' f kind scan =
  command3 (fn f => command00 (drop2 f) kind scan) f

end

ML ― ‹analogous to 🗏‹~~/src/Pure/ML/ml_file.ML› signature C_INNER_FILE =
 sig
    val C: (theory -> Token.file) -> generic_theory -> generic_theory
    val ML: bool option -> (theory -> Token.file) -> generic_theory -> generic_theory
    val SML: bool option -> (theory -> Token.file) -> generic_theory -> generic_theory
    val command_c: Token.file -> generic_theory -> generic_theory
    val command_ml: string -> bool -> bool option -> (theory -> Token.file) 
                     -> Context.generic -> generic_theory
  end

structure C_Inner_File : C_INNER_FILE =
struct

fun command_c ({lines, pos, ...}: Token.file) =
  C_Module.C (Input.source true (cat_lines lines) (pos, pos));

fun C get_file gthy =
  command_c (get_file (Context.theory_of gthy)) gthy;

fun command_ml environment catch_all debug get_file gthy =
  let
    val file = get_file (Context.theory_of gthy);
    val source = Token.file_source file;

    val _ = Document_Output.check_comments (Context.proof_of gthy) (Input.source_explode source);

    val flags: ML_Compiler.flags =
      {environment = environment, redirect = true, verbose = true, catch_all = catch_all,
        debug = debug, writeln = writeln, warning = warning};
  in
    gthy
    |> ML_Context.exec (fn () => ML_Context.eval_source flags source)
    |> Local_Theory.propagate_ml_env
  end;

val ML = command_ml "" false;
val SML = command_ml ML_Env.SML true;
end;

subsubsection ‹Initialization›

setup ― ‹analogous to theoryPure C_Thy_Header.add_keywords_minor
  (maps (fn ((name, pos_lex, pos_bot, pos_top), ty) =>
          [ ((C_Inner_Syntax.pref_lex name, pos_lex), ty)
          , ((C_Inner_Syntax.pref_bot name, pos_bot), ty)
          , ((C_Inner_Syntax.pref_top name, pos_top), ty) ])
        [ (("apply", , , ), Keyword.command_spec (Keyword.prf_script, ["proof"]))
        , (("by", , , ), Keyword.command_spec (Keyword.qed, ["proof"]))
        , (("done", , , ), Keyword.command_spec (Keyword.qed_script, ["proof"])) ])

ML ― ‹analogous to theoryPure signature C_ISAR_CMD =

  sig
    val ML     :    Input.source -> generic_theory -> generic_theory
    val text   :    Input.source -> generic_theory -> generic_theory
    val declare:    (Facts.ref * Token.src list) list list * 
                    (binding * string option * mixfix) list 
                    -> bool 
                    -> local_theory -> local_theory
    val definition: (((binding * string option * mixfix) option 
                      * (Attrib.binding * string)) 
                      * string list) 
                    * (binding * string option * mixfix) list
                    -> bool 
                    -> local_theory -> local_theory
    val theorem:  bool ->
                   (bool * Attrib.binding * Bundle.xname list 
                    * Element.context list * Element.statement) 
                   * (Method.text_range list 
                      * (Method.text_range * Method.text_range option) option)
                   -> bool 
                   -> local_theory -> local_theory
  end

local
val semi = Scan.option (C_Parse.$$$ ";");

structure C_Isar_Cmd : C_ISAR_CMD = 
struct
fun ML source = ML_Context.exec (fn () =>
                   ML_Context.eval_source (ML_Compiler.verbose true ML_Compiler.flags) source) #>
                 Local_Theory.propagate_ml_env

fun output ctxt markdown markup txt  =
      let
        val _ = Context_Position.reports ctxt (Document_Output.document_reports txt);
      in txt |> Document_Output.output_document ctxt {markdown = markdown} |> markup end;

fun text source = ML_Context.exec (fn () =>
                   ML_Context.eval_source (ML_Compiler.verbose true ML_Compiler.flags) source) #>
                 Local_Theory.propagate_ml_env

fun theorem schematic ((long, binding, includes, elems, concl), (l_meth, o_meth)) int lthy =
     (if schematic then Specification.schematic_theorem_cmd else Specification.theorem_cmd)
       long Thm.theoremK NONE (K I) binding includes elems concl int lthy
  |> fold (fn m => tap (fn _ => Method.report m) #> Proof.apply m #> Seq.the_result "") l_meth
  |> (case o_meth of
        NONE => Proof.global_done_proof
      | SOME (m1, m2) =>
          tap (fn _ => (Method.report m1; Option.map Method.report m2))
          #> Proof.global_terminal_proof (m1, m2))

fun definition (((decl, spec), prems), params) =
  #2 oo Specification.definition_cmd decl params prems spec

fun declare (facts, fixes) =
  #2 oo Specification.theorems_cmd "" [(Binding.empty_atts, flat facts)] fixes
end

local
val long_keyword =
  Parse_Spec.includes >> K "" ||
  Parse_Spec.long_statement_keyword;

val long_statement =
  Scan.optional (Parse_Spec.opt_thm_name ":" --| Scan.ahead long_keyword) Binding.empty_atts --
  Scan.optional Parse_Spec.includes [] -- Parse_Spec.long_statement
    >> (fn ((binding, includes), (elems, concl)) => (true, binding, includes, elems, concl));

val short_statement =
  Parse_Spec.statement -- Parse_Spec.if_statement -- Parse.for_fixes
    >> (fn ((shows, assumes), fixes) =>
      (false, Binding.empty_atts, [], [Element.Fixes fixes, Element.Assumes assumes],
        Element.Shows shows));
in
fun theorem spec schematic =
  C_Inner_Syntax.local_command'
    spec
    (fn name_pref =>
      (long_statement || short_statement)
      -- let val apply = Parse.$$$ (name_pref "apply") |-- Method.parse
         in Scan.repeat1 apply -- (Parse.$$$ (name_pref "done") >> K NONE)
         || Scan.repeat apply -- (Parse.$$$ (name_pref "by")
                                  |-- Method.parse -- Scan.option Method.parse >> SOME)
         end)
    (C_Isar_Cmd.theorem schematic)
end

val opt_modes =
  Scan.optional (keyword( |-- Parse.!!! (Scan.repeat1 Parse.name --| keyword))) [];

val _ = C_Inner_Syntax.command0':
          ('a -> Context.generic -> Context.generic) 
        -> string 
        -> 'a C_Parse.parser 
        -> string * Position.T * Position.T * Position.T -> theory -> theory

val _ = Theory.setup
 (   C_Inner_Syntax.command  (C_Inner_Toplevel.generic_theory oo C_Inner_Isar_Cmd.setup)
                             C_Parse.ML_source
                             ("≈setup", , )
  #> C_Inner_Syntax.command0 (C_Inner_Toplevel.theory o Isar_Cmd.setup)
                             C_Parse.ML_source
                             ("setup", , , )
  #> C_Inner_Syntax.command0 (C_Inner_Toplevel.generic_theory o C_Isar_Cmd.ML)
                             C_Parse.ML_source
                             ("ML", , , )
  #> C_Inner_Syntax.command0 (C_Inner_Toplevel.generic_theory o C_Isar_Cmd.text)
                             C_Parse.document_source
                             ("text", , , )
  #> C_Inner_Syntax.command0 (C_Inner_Toplevel.generic_theory o C_Module.C)
                             C_Parse.C_source
                             ("C", , , )
  #> C_Inner_Syntax.command0'(C_Inner_Toplevel.generic_theory o C_Inner_File.ML NONE)
                             Keyword.thy_load
                             (C_Resources.parse_file --| semi)
                             ("ML_file", , , )
  #> C_Inner_Syntax.command0'(C_Inner_Toplevel.generic_theory o C_Inner_File.C)
                             Keyword.thy_load
                             (C_Resources.parse_file --| semi)
                             ("C_file", , , )
  #> C_Inner_Syntax.command0 (C_Inner_Toplevel.generic_theory o C_Module.C_export_boot)
                             C_Parse.C_source
                             ("C_export_boot", , , )
  #> C_Inner_Syntax.command_range'
                             (Context.map_theory o Named_Target.theory_map o C_Module.C_export_file)
                             ("C_export_file", , , )
  #> C_Inner_Syntax.command_no_range
       (C_Inner_Toplevel.generic_theory oo C_Inner_Isar_Cmd.setup
         fn ((_, (_, pos1, pos2)) :: _) =>
              (fn _ => fn _ =>
                tap (fn _ =>
                      Position.reports_text [((Position.range (pos1, pos2)
                                               |> Position.range_position, Markup.intensify), "")]))
           | _ => fn _ => fn _ => I›)
       ("highlight", , )
  #> theorem ("theorem", , , ) false
  #> theorem ("lemma", , , ) false
  #> theorem ("corollary", , , ) false
  #> theorem ("proposition", , , ) false
  #> theorem ("schematic_goal", , , ) true
  #> C_Inner_Syntax.local_command''
      ("definition", , , )
      (Scan.option Parse_Spec.constdecl -- (Parse_Spec.opt_thm_name ":" -- Parse.prop) --
        Parse_Spec.if_assumes -- Parse.for_fixes)
      C_Isar_Cmd.definition
  #> C_Inner_Syntax.local_command''
      ("declare", , , )
      (Parse.and_list1 Parse.thms1 -- Parse.for_fixes)
      C_Isar_Cmd.declare
  #> C_Inner_Syntax.command0
      (C_Inner_Toplevel.keep'' o C_Inner_Isar_Cmd.print_term)
      (C_Token.syntax' (opt_modes -- Parse.term))
      ("term", , , ))
in  end


subsection ‹Definitions of Outer Classical Commands›
subsubsection ‹Library›
(*  Author:     Frédéric Tuong, Université Paris-Saclay
    Analogous to:
(*  Title:      Pure/Pure.thy
    Author:     Makarius

The Pure theory, with definitions of Isar commands and some lemmas.
*)*)
ML ― ‹analogously to 🗏‹~~/src/Pure/Isar/parse.ML› structure C_Outer_Parse : 
          sig val C_source: Input.source parser end =
struct
  val C_source = Parse.input (Parse.group (fn () => "C source") Parse.embedded)
end

ML ― ‹analogously to 🗏‹~~/src/Pure/Isar/outer_syntax.ML› structure C_Outer_Syntax =
struct
val _ =
  Outer_Syntax.command command_keywordC ""
    (C_Outer_Parse.C_source >> (Toplevel.generic_theory o C_Module.C));
end

ML ― ‹analogously to 🗏‹~~/src/Pure/Isar/isar_cmd.ML› signature C_OUTER_ISAR_CMD =
  sig
    val C_diag: Input.source -> Toplevel.state -> unit
    structure Diag_State: PROOF_DATA
    val diag_goal: Proof.context -> {context: Proof.context, facts: thm list, goal: thm}
    val diag_state: Proof.context -> Toplevel.state
  end

structure C_Outer_Isar_Cmd : C_OUTER_ISAR_CMD =
struct
(* diagnostic ML evaluation *)

structure Diag_State = Proof_Data
(
  type T = Toplevel.state option;
  fun init _ = NONE;
);

fun C_diag source state =
  let
    val opt_ctxt =
      try Toplevel.generic_theory_of state
      |> Option.map (Context.proof_of #> Diag_State.put (SOME state));
  in Context.setmp_generic_context (Option.map Context.Proof opt_ctxt)
    (fn () => C_Module.eval_source source) () end;

fun diag_state ctxt =
  (case Diag_State.get ctxt of
    SOME st => st
  | NONE => Toplevel.make_state NONE);

val diag_goal = Proof.goal o Toplevel.proof_of o diag_state;

val _ = Theory.setup
  (ML_Antiquotation.value (Binding.qualify true "Isar" bindingC_state)
    (Scan.succeed "C_Outer_Isar_Cmd.diag_state ML_context") #>
   ML_Antiquotation.value (Binding.qualify true "Isar" bindingC_goal)
    (Scan.succeed "C_Outer_Isar_Cmd.diag_goal ML_context"));

end

ML ― ‹analogously to 🗏‹~~/src/Pure/ML/ml_file.ML› structure C_Outer_File : sig
    val C: (theory -> Token.file) -> Context.generic -> Context.generic
  (*  val command_c: Token.file -> Context.generic -> Context.generic *)
  end =
struct

fun command_c ({src_path, lines, digest, pos}: Token.file) =
  let
    val provide = Resources.provide (src_path, digest);
  in I
     #> C_Module.C (Input.source true (cat_lines lines) (pos, pos))
     #> Context.mapping provide (Local_Theory.background_theory provide)
  end;

fun C get_file gthy =
  command_c (get_file (Context.theory_of gthy)) gthy;

end;

subsubsection ‹Setup for  ‹C› and ‹C_file› Command Syntax›

ML local

val semi = Scan.option keyword;;

val _ =
  Outer_Syntax.command command_keywordC_file "read and evaluate Isabelle/C file"
    (Resources.parse_file --| semi >> (Toplevel.generic_theory o C_Outer_File.C));

val _ =
  Outer_Syntax.command command_keywordC_export_boot
    "C text within theory or local theory, and export to bootstrap environment"
    (C_Outer_Parse.C_source >> (Toplevel.generic_theory o C_Module.C_export_boot));

val _ =
  Outer_Syntax.command command_keywordC_prf "C text within proof"
    (C_Outer_Parse.C_source >> (Toplevel.proof o C_Module.C_prf));

val _ =
  Outer_Syntax.command command_keywordC_val "diagnostic C text"
    (C_Outer_Parse.C_source >> (Toplevel.keep o C_Outer_Isar_Cmd.C_diag));

val _ =
  Outer_Syntax.local_theory command_keywordC_export_file "diagnostic C text"
    (Scan.succeed () >> K (C_Module.C_export_file Position.no_range));
in end

subsection ‹Term-Cartouches for C Syntax›

syntax "_C_translation_unit" :: cartouche_position  string (Cunit _›)
syntax "_C_external_declaration" :: cartouche_position  string (Cdecl _›)
syntax "_C_expression" :: cartouche_position  string (Cexpr _›)
syntax "_C_statement" :: cartouche_position  string (Cstmt _›)
syntax "_C" :: cartouche_position  string (C _›)

parse_translation C_Module.C_Term'.parse_translation
  [ (syntax_const‹_C_translation_unit›, SOME C_Module.C_Term.tok_translation_unit)
  , (syntax_const‹_C_external_declaration›, SOME C_Module.C_Term.tok_external_declaration)
  , (syntax_const‹_C_expression›, SOME C_Module.C_Term.tok_expression)
  , (syntax_const‹_C_statement›, SOME C_Module.C_Term.tok_statement)
  , (syntax_const‹_C›, NONE) ]

(*test*)
MLC_Module.env (Context.the_generic_context())

subsection‹C-env related ML-Antiquotations as Programming Support›

ML(*
was in Isabelle2020: 
    (Args.context -- Scan.lift Args.embedded_position >> (fn (ctxt, (name, pos)) =>

with:

val embedded_token = ident || string || cartouche;
val embedded_inner_syntax = embedded_token >> Token.inner_syntax_of;
val embedded_input = embedded_token >> Token.input_of;
val embedded = embedded_token >> Token.content_of;
val embedded_position = embedded_input >> Input.source_content;

defined in args.

Setting it to :

    (Args.context -- Scan.lift Args.name_position >> (fn (ctxt, (name, pos)) =>

makes this syntactically more restrictive. 
*)

val _ = Theory.setup(
  ML_Antiquotation.value_embedded bindingCenv
    (Args.context -- Scan.lift Args.name_position >> (fn (ctxt, (name, pos)) =>
      (warning"arg variant not implemented";"C_Module.env (Context.the_generic_context())"))
    || Scan.succeed "C_Module.env (Context.the_generic_context())"))

text‹Note that this anti-quotation is controlled by the ‹C_starting_env› - flag.  ›    

declare[[Cenv0 = last]]
ML@{Cenv}

declare[[Cenv0 = empty]]
ML@{Cenv}

subsection‹The Standard Store C11-AST's generated from C-commands›
text‹Each call of the C command will register the parsed root AST in this theory-name indexed table.›

MLstructure Root_Ast_Store = Generic_Data
  (type T = C_Grammar_Rule.ast_generic list Symtab.table
   val empty = Symtab.empty
   val extend = I
   val merge = K empty);


Root_Ast_Store.map: (   C_Grammar_Rule.ast_generic list Symtab.table 
                            -> C_Grammar_Rule.ast_generic list Symtab.table) 
                        -> Context.generic -> Context.generic;


fun update_Root_Ast filter ast _ ctxt =
    let val theory_id = Context.theory_long_name(Context.theory_of ctxt)
        val insert_K_ast  = Symtab.map_default (theory_id,[]) (cons ast)
    in  case filter ast of 
         NONE => (warning "No appropriate c11 ast found - store unchanged."; ctxt)
        |SOME _ => (Root_Ast_Store.map insert_K_ast) ctxt
    end;


fun get_Root_Ast filter thy =
  let val ctxt = Context.Theory thy
      val thid = Context.theory_long_name(Context.theory_of ctxt)
      val ast = case Symtab.lookup (Root_Ast_Store.get ctxt) (thid) of
                SOME (a::_) => (case filter a of 
                                 NONE => error "Last C command is not of appropriate AST-class."
                               | SOME x => x)
              | _ => error"No C command in the current theory."
  in ast
  end

val get_CExpr  = get_Root_Ast C_Grammar_Rule.get_CExpr;
val get_CStat  = get_Root_Ast C_Grammar_Rule.get_CStat;
val get_CExtDecl  = get_Root_Ast C_Grammar_Rule.get_CExtDecl;
val get_CTranslUnit  = get_Root_Ast C_Grammar_Rule.get_CTranslUnit;

setup Context.theory_map (C_Module.Data_Accept.put (update_Root_Ast SOME))


ML(* Was : Args.embedded_position changed to : Args.name_position.
  See comment above. *)
val _ = Theory.setup(
        ML_Antiquotation.value_embedded bindingC11_CTranslUnit
          (Args.context -- Scan.lift Args.name_position >> (fn (ctxt, (name, pos)) =>
            (warning"arg variant not implemented";"get_CTranslUnit (Context.the_global_context())"))
          || Scan.succeed "get_CTranslUnit (Context.the_global_context())")
        #> 
        ML_Antiquotation.value_embedded bindingC11_CExtDecl
          (Args.context -- Scan.lift Args.name_position >> (fn (ctxt, (name, pos)) =>
            (warning"arg variant not implemented";"get_CExtDecl (Context.the_global_context())"))
          || Scan.succeed "get_CExtDecl (Context.the_global_context())")
        #> 
        ML_Antiquotation.value_embedded bindingC11_CStat
          (Args.context -- Scan.lift Args.name_position >> (fn (ctxt, (name, pos)) =>
            (warning"arg variant not implemented";"get_CStat (Context.the_global_context())"))
          || Scan.succeed "get_CStat (Context.the_global_context())")
        #> 
        ML_Antiquotation.value_embedded bindingC11_CExpr
          (Args.context -- Scan.lift Args.name_position >> (fn (ctxt, (name, pos)) =>
            (warning"arg variant not implemented";"get_CExpr (Context.the_global_context())"))
          || Scan.succeed "get_CExpr (Context.the_global_context())")
       )

end