src/Pure/Isar/toplevel.ML
author berghofe
Tue Aug 28 18:04:21 2007 +0200 (2007-08-28 ago)
changeset 24453 86cf57ddf8f6
parent 24295 af8dbc7a2305
child 24634 38db11874724
permissions -rw-r--r--
Added local_theory_to_proof'
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(*  Title:      Pure/Isar/toplevel.ML
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    ID:         $Id$
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    Author:     Markus Wenzel, TU Muenchen
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The Isabelle/Isar toplevel.
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*)
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signature TOPLEVEL =
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sig
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  exception UNDEF
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  type generic_theory
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  type node
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  val theory_node: node -> generic_theory option
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  val proof_node: node -> ProofHistory.T option
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  val cases_node: (generic_theory -> 'a) -> (Proof.state -> 'a) -> node -> 'a
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  val presentation_context: node option -> xstring option -> Proof.context
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  type state
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  val is_toplevel: state -> bool
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  val is_theory: state -> bool
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  val is_proof: state -> bool
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  val level: state -> int
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  val node_history_of: state -> node History.T
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  val node_of: state -> node
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  val node_case: (generic_theory -> 'a) -> (Proof.state -> 'a) -> state -> 'a
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  val context_of: state -> Proof.context
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  val generic_theory_of: state -> generic_theory
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  val theory_of: state -> theory
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  val proof_of: state -> Proof.state
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  val proof_position_of: state -> int
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  val enter_proof_body: state -> Proof.state
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  val print_state_context: state -> unit
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  val print_state: bool -> state -> unit
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  val quiet: bool ref
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  val debug: bool ref
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  val interact: bool ref
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  val timing: bool ref
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  val profiling: int ref
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  val skip_proofs: bool ref
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  exception TERMINATE
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  exception RESTART
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  exception TOPLEVEL_ERROR
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  val exn_message: exn -> string
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  val program: (unit -> 'a) -> 'a
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  type transition
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  val undo_limit: bool -> int option
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  val empty: transition
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  val name_of: transition -> string
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  val source_of: transition -> OuterLex.token list option
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  val name: string -> transition -> transition
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  val position: Position.T -> transition -> transition
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  val source: OuterLex.token list -> transition -> transition
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  val interactive: bool -> transition -> transition
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  val print: transition -> transition
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  val print': string -> transition -> transition
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  val three_buffersN: string
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  val print3: transition -> transition
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  val no_timing: transition -> transition
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  val init_theory: (bool -> theory) -> (theory -> unit) -> (theory -> unit) ->
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    transition -> transition
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  val init_empty: (unit -> unit) -> transition -> transition
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  val exit: transition -> transition
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  val undo_exit: transition -> transition
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  val kill: transition -> transition
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  val history: (node History.T -> node History.T) -> transition -> transition
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  val keep: (state -> unit) -> transition -> transition
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  val keep': (bool -> state -> unit) -> transition -> transition
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  val imperative: (unit -> unit) -> transition -> transition
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  val theory: (theory -> theory) -> transition -> transition
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  val theory': (bool -> theory -> theory) -> transition -> transition
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  val begin_local_theory: bool -> (theory -> local_theory) -> transition -> transition
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  val end_local_theory: transition -> transition
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  val local_theory: xstring option -> (local_theory -> local_theory) -> transition -> transition
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  val present_local_theory: xstring option -> (bool -> node -> unit) -> transition -> transition
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  val local_theory_to_proof': xstring option -> (bool -> local_theory -> Proof.state) ->
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    transition -> transition
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  val local_theory_to_proof: xstring option -> (local_theory -> Proof.state) ->
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    transition -> transition
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  val theory_to_proof: (theory -> Proof.state) -> transition -> transition
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  val end_proof: (bool -> Proof.state -> Proof.context) -> transition -> transition
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  val forget_proof: transition -> transition
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  val present_proof: (bool -> node -> unit) -> transition -> transition
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  val proofs': (bool -> Proof.state -> Proof.state Seq.seq) -> transition -> transition
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  val proof': (bool -> Proof.state -> Proof.state) -> transition -> transition
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  val proofs: (Proof.state -> Proof.state Seq.seq) -> transition -> transition
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  val proof: (Proof.state -> Proof.state) -> transition -> transition
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  val actual_proof: (ProofHistory.T -> ProofHistory.T) -> transition -> transition
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  val skip_proof: (int History.T -> int History.T) -> transition -> transition
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  val skip_proof_to_theory: (int -> bool) -> transition -> transition
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  val unknown_theory: transition -> transition
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  val unknown_proof: transition -> transition
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  val unknown_context: transition -> transition
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  val present_excursion: (transition * (state -> state -> 'a -> 'a)) list -> 'a -> 'a
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  val excursion: transition list -> unit
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  val set_state: state -> unit
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  val get_state: unit -> state
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  val exn: unit -> (exn * string) option
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  val >> : transition -> bool
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  val >>> : transition list -> unit
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  val init_state: unit -> unit
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  type 'a isar
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  val loop: 'a isar -> unit
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end;
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structure Toplevel: TOPLEVEL =
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struct
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(** toplevel state **)
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exception UNDEF;
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(* local theory wrappers *)
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type generic_theory = Context.generic;    (*theory or local_theory*)
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val loc_init = TheoryTarget.init;
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val loc_exit = ProofContext.theory_of o LocalTheory.exit;
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fun loc_begin loc (Context.Theory thy) = loc_init loc thy
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  | loc_begin NONE (Context.Proof lthy) = lthy
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  | loc_begin loc (Context.Proof lthy) = loc_init loc (loc_exit lthy);
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fun loc_finish _ (Context.Theory _) = Context.Theory o loc_exit
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  | loc_finish NONE (Context.Proof _) = Context.Proof o LocalTheory.restore
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  | loc_finish (SOME _) (Context.Proof lthy) = Context.Proof o LocalTheory.reinit lthy o loc_exit;
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(* datatype node *)
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datatype node =
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  Theory of generic_theory * Proof.context option | (*theory with presentation context*)
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  Proof of ProofHistory.T * ((Proof.context -> generic_theory) * generic_theory) |
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    (*history of proof states, finish, original theory*)
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  SkipProof of int History.T * (generic_theory * generic_theory);
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    (*history of proof depths, resulting theory, original theory*)
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val the_global_theory = fn Theory (Context.Theory thy, _) => thy | _ => raise UNDEF;
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val theory_node = fn Theory (gthy, _) => SOME gthy | _ => NONE;
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val proof_node = fn Proof (prf, _) => SOME prf | _ => NONE;
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fun cases_node f _ (Theory (gthy, _)) = f gthy
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  | cases_node _ g (Proof (prf, _)) = g (ProofHistory.current prf)
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  | cases_node f _ (SkipProof (_, (gthy, _))) = f gthy;
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fun presentation_context (SOME (Theory (_, SOME ctxt))) NONE = ctxt
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  | presentation_context (SOME node) NONE = cases_node Context.proof_of Proof.context_of node
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  | presentation_context (SOME node) (SOME loc) =
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      loc_init (SOME loc) (cases_node Context.theory_of Proof.theory_of node)
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  | presentation_context NONE _ = raise UNDEF;
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(* datatype state *)
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type state_info = node History.T * ((theory -> unit) * (theory -> unit));
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datatype state =
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  Toplevel of state_info option |  (*outer toplevel, leftover end state*)
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  State of state_info;
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val toplevel = Toplevel NONE;
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fun is_toplevel (Toplevel _) = true
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  | is_toplevel _ = false;
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fun level (Toplevel _) = 0
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  | level (State (node, _)) =
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      (case History.current node of
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        Theory _ => 0
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      | Proof (prf, _) => Proof.level (ProofHistory.current prf)
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      | SkipProof (h, _) => History.current h + 1);   (*different notion of proof depth!*)
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fun str_of_state (Toplevel _) = "at top level"
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  | str_of_state (State (node, _)) =
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      (case History.current node of
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        Theory (Context.Theory _, _) => "in theory mode"
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      | Theory (Context.Proof _, _) => "in local theory mode"
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      | Proof _ => "in proof mode"
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      | SkipProof _ => "in skipped proof mode");
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(* top node *)
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fun node_history_of (Toplevel _) = raise UNDEF
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  | node_history_of (State (node, _)) = node;
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val node_of = History.current o node_history_of;
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fun is_theory state = not (is_toplevel state) andalso is_some (theory_node (node_of state));
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fun is_proof state = not (is_toplevel state) andalso is_some (proof_node (node_of state));
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fun node_case f g state = cases_node f g (node_of state);
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val context_of = node_case Context.proof_of Proof.context_of;
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val generic_theory_of = node_case I (Context.Proof o Proof.context_of);
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val theory_of = node_case Context.theory_of Proof.theory_of;
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val proof_of = node_case (fn _ => raise UNDEF) I;
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fun proof_position_of state =
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  (case node_of state of
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    Proof (prf, _) => ProofHistory.position prf
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  | _ => raise UNDEF);
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val enter_proof_body = node_case (Proof.init o Context.proof_of) Proof.enter_forward;
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(* print state *)
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val pretty_context = LocalTheory.pretty o Context.cases (loc_init NONE) I;
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fun print_state_context state =
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  (case try (node_case I (Context.Proof o Proof.context_of)) state of
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    NONE => []
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  | SOME gthy => pretty_context gthy)
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  |> Pretty.chunks |> Pretty.writeln;
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fun print_state prf_only state =
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  (case try node_of state of
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    NONE => []
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  | SOME (Theory (gthy, _)) => if prf_only then [] else pretty_context gthy
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  | SOME (Proof (prf, _)) =>
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      Proof.pretty_state (ProofHistory.position prf) (ProofHistory.current prf)
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  | SOME (SkipProof (h, _)) =>
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      [Pretty.str ("skipped proof: depth " ^ string_of_int (History.current h))])
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  |> Pretty.markup_chunks Markup.state |> Pretty.writeln;
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(** toplevel transitions **)
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val quiet = ref false;
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val debug = Output.debugging;
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val interact = ref false;
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val timing = Output.timing;
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val profiling = ref 0;
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val skip_proofs = ref false;
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exception TERMINATE;
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exception RESTART;
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exception EXCURSION_FAIL of exn * string;
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exception FAILURE of state * exn;
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exception TOPLEVEL_ERROR;
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(* print exceptions *)
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local
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fun with_context f xs =
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  (case ML_Context.get_context () of NONE => []
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  | SOME context => map (f (Context.proof_of context)) xs);
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fun raised name [] = "exception " ^ name ^ " raised"
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  | raised name [msg] = "exception " ^ name ^ " raised: " ^ msg
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  | raised name msgs = cat_lines (("exception " ^ name ^ " raised:") :: msgs);
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fun exn_msg _ TERMINATE = "Exit."
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  | exn_msg _ RESTART = "Restart."
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  | exn_msg _ Interrupt = "Interrupt."
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  | exn_msg _ TOPLEVEL_ERROR = "Error."
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  | exn_msg _ (SYS_ERROR msg) = "## SYSTEM ERROR ##\n" ^ msg
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  | exn_msg _ (ERROR msg) = msg
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  | exn_msg detailed (Exn.EXCEPTIONS (exns, "")) = cat_lines (map (exn_msg detailed) exns)
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  | exn_msg detailed (Exn.EXCEPTIONS (exns, msg)) = cat_lines (map (exn_msg detailed) exns @ [msg])
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  | exn_msg detailed (EXCURSION_FAIL (exn, msg)) = cat_lines [exn_msg detailed exn, msg]
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  | exn_msg false (THEORY (msg, _)) = msg
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  | exn_msg true (THEORY (msg, thys)) = raised "THEORY" (msg :: map Context.str_of_thy thys)
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  | exn_msg false (Syntax.AST (msg, _)) = raised "AST" [msg]
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  | exn_msg true (Syntax.AST (msg, asts)) =
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      raised "AST" (msg :: map (Pretty.string_of o Syntax.pretty_ast) asts)
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  | exn_msg false (TYPE (msg, _, _)) = raised "TYPE" [msg]
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  | exn_msg true (TYPE (msg, Ts, ts)) = raised "TYPE" (msg ::
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        with_context ProofContext.string_of_typ Ts @ with_context ProofContext.string_of_term ts)
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  | exn_msg false (TERM (msg, _)) = raised "TERM" [msg]
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  | exn_msg true (TERM (msg, ts)) =
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      raised "TERM" (msg :: with_context ProofContext.string_of_term ts)
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  | exn_msg false (THM (msg, _, _)) = raised "THM" [msg]
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  | exn_msg true (THM (msg, i, thms)) =
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      raised ("THM " ^ string_of_int i) (msg :: with_context ProofContext.string_of_thm thms)
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  | exn_msg _ Option.Option = raised "Option" []
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  | exn_msg _ Library.UnequalLengths = raised "UnequalLengths" []
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  | exn_msg _ Empty = raised "Empty" []
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  | exn_msg _ Subscript = raised "Subscript" []
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  | exn_msg _ (Fail msg) = raised "Fail" [msg]
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  | exn_msg _ exn = General.exnMessage exn;
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in
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fun exn_message exn = exn_msg (! debug) exn;
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fun print_exn NONE = ()
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  | print_exn (SOME (exn, s)) = Output.error_msg (cat_lines [exn_message exn, s]);
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end;
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(* controlled execution *)
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local
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fun debugging f x =
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  if ! debug then exception_trace (fn () => f x)
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  else f x;
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fun interruptible f x =
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  let val y = ref x
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  in raise_interrupt (fn () => y := f x) (); ! y end;
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fun toplevel_error f x = f x
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  handle exn => (Output.error_msg (exn_message exn); raise TOPLEVEL_ERROR);
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in
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fun controlled_execution f =
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  f
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  |> debugging
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  |> interruptible;
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fun program f =
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 (f
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  |> debugging
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  |> toplevel_error) ();
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end;
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(* node transactions and recovery from stale theories *)
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(*NB: proof commands should be non-destructive!*)
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local
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fun is_stale state = Context.is_stale (theory_of state) handle UNDEF => false;
wenzelm@6689
   335
wenzelm@18685
   336
val stale_theory = ERROR "Stale theory encountered after succesful execution!";
wenzelm@16815
   337
wenzelm@23363
   338
fun map_theory f = History.map_current
wenzelm@21177
   339
  (fn Theory (gthy, _) => Theory (Context.mapping f (LocalTheory.raw_theory f) gthy, NONE)
wenzelm@21177
   340
    | node => node);
wenzelm@6689
   341
wenzelm@23363
   342
fun context_position pos = History.map_current
wenzelm@23363
   343
  (fn Theory (Context.Proof lthy, ctxt) =>
wenzelm@23363
   344
        Theory (Context.Proof (ContextPosition.put pos lthy), ctxt)
wenzelm@23363
   345
    | Proof (prf, x) =>
wenzelm@23363
   346
        Proof (ProofHistory.map_current (Proof.map_context (ContextPosition.put pos)) prf, x)
wenzelm@23363
   347
    | node => node);
wenzelm@23363
   348
skalberg@15531
   349
fun return (result, NONE) = result
skalberg@15531
   350
  | return (result, SOME exn) = raise FAILURE (result, exn);
wenzelm@7022
   351
wenzelm@6689
   352
in
wenzelm@6689
   353
wenzelm@23363
   354
fun transaction hist pos f (node, term) =
wenzelm@20128
   355
  let
wenzelm@21177
   356
    val cont_node = map_theory Theory.checkpoint node;
wenzelm@21177
   357
    val back_node = map_theory Theory.copy cont_node;
wenzelm@21958
   358
    fun state nd = State (nd, term);
wenzelm@20128
   359
    fun normal_state nd = (state nd, NONE);
wenzelm@20128
   360
    fun error_state nd exn = (state nd, SOME exn);
wenzelm@6689
   361
wenzelm@20128
   362
    val (result, err) =
wenzelm@20128
   363
      cont_node
wenzelm@23363
   364
      |> context_position pos
wenzelm@20128
   365
      |> (f
wenzelm@23363
   366
          |> (if hist then History.apply' (History.current back_node) else History.map_current)
wenzelm@20128
   367
          |> controlled_execution)
wenzelm@23363
   368
      |> context_position Position.none
wenzelm@20128
   369
      |> normal_state
wenzelm@20128
   370
      handle exn => error_state cont_node exn;
wenzelm@20128
   371
  in
wenzelm@20128
   372
    if is_stale result
wenzelm@20128
   373
    then return (error_state back_node (the_default stale_theory err))
wenzelm@20128
   374
    else return (result, err)
wenzelm@20128
   375
  end;
wenzelm@6689
   376
wenzelm@6689
   377
end;
wenzelm@6689
   378
wenzelm@6689
   379
wenzelm@6689
   380
(* primitive transitions *)
wenzelm@6689
   381
wenzelm@18563
   382
(*Note: Recovery from stale theories is provided only for theory-level
wenzelm@18589
   383
  operations via Transaction.  Other node or state operations should
wenzelm@18589
   384
  not touch theories at all.  Interrupts are enabled only for Keep and
wenzelm@18589
   385
  Transaction.*)
wenzelm@5828
   386
wenzelm@5828
   387
datatype trans =
wenzelm@22056
   388
  Init of (bool -> theory) * ((theory -> unit) * (theory -> unit)) |
wenzelm@21958
   389
                                                    (*init node; with exit/kill operation*)
wenzelm@23911
   390
  InitEmpty of unit -> unit |                       (*init empty toplevel*)
wenzelm@21958
   391
  Exit |                                            (*conclude node -- deferred until init*)
wenzelm@21958
   392
  UndoExit |                                        (*continue after conclusion*)
wenzelm@21958
   393
  Kill |                                            (*abort node*)
wenzelm@21958
   394
  History of node History.T -> node History.T |     (*history operation (undo etc.)*)
wenzelm@21958
   395
  Keep of bool -> state -> unit |                   (*peek at state*)
wenzelm@21958
   396
  Transaction of bool * (bool -> node -> node);     (*node transaction*)
wenzelm@6689
   397
skalberg@15531
   398
fun undo_limit int = if int then NONE else SOME 0;
wenzelm@6689
   399
wenzelm@22056
   400
fun safe_exit (Toplevel (SOME (node, (exit, _)))) =
wenzelm@22056
   401
    (case try the_global_theory (History.current node) of
wenzelm@22056
   402
      SOME thy => exit thy
wenzelm@22056
   403
    | NONE => ())
wenzelm@22056
   404
  | safe_exit _ = ();
wenzelm@21958
   405
wenzelm@6689
   406
local
wenzelm@5828
   407
wenzelm@21958
   408
fun keep_state int f = controlled_execution (fn x => tap (f int) x);
wenzelm@21958
   409
wenzelm@23363
   410
fun apply_tr int _ (Init (f, term)) (state as Toplevel _) =
wenzelm@22056
   411
      let val node = Theory (Context.Theory (f int), NONE)
wenzelm@22056
   412
      in safe_exit state; State (History.init (undo_limit int) node, term) end
wenzelm@23911
   413
  | apply_tr int _ (InitEmpty f) (state as Toplevel _) =
wenzelm@23911
   414
      (safe_exit state; keep_state int (fn _ => fn _ => f ()) toplevel)
wenzelm@23363
   415
  | apply_tr _ _ Exit (State (node, term)) =
wenzelm@22056
   416
      (the_global_theory (History.current node); Toplevel (SOME (node, term)))
wenzelm@23363
   417
  | apply_tr _ _ UndoExit (Toplevel (SOME state_info)) = State state_info
wenzelm@23363
   418
  | apply_tr _ _ Kill (State (node, (_, kill))) =
wenzelm@22056
   419
      (kill (the_global_theory (History.current node)); toplevel)
wenzelm@23363
   420
  | apply_tr _ _ (History f) (State (node, term)) = State (f node, term)
wenzelm@23363
   421
  | apply_tr int _ (Keep f) state = keep_state int f state
wenzelm@23363
   422
  | apply_tr int pos (Transaction (hist, f)) (State state) =
wenzelm@23363
   423
      transaction hist pos (fn x => f int x) state
wenzelm@23363
   424
  | apply_tr _ _ _ _ = raise UNDEF;
wenzelm@5828
   425
wenzelm@23363
   426
fun apply_union _ _ [] state = raise FAILURE (state, UNDEF)
wenzelm@23363
   427
  | apply_union int pos (tr :: trs) state =
wenzelm@23363
   428
      apply_tr int pos tr state
wenzelm@23363
   429
        handle UNDEF => apply_union int pos trs state
wenzelm@23363
   430
          | FAILURE (alt_state, UNDEF) => apply_union int pos trs alt_state
wenzelm@6689
   431
          | exn as FAILURE _ => raise exn
wenzelm@6689
   432
          | exn => raise FAILURE (state, exn);
wenzelm@6689
   433
wenzelm@6689
   434
in
wenzelm@6689
   435
wenzelm@23363
   436
fun apply_trans int pos trs state = (apply_union int pos trs state, NONE)
skalberg@15531
   437
  handle FAILURE (alt_state, exn) => (alt_state, SOME exn) | exn => (state, SOME exn);
wenzelm@6689
   438
wenzelm@6689
   439
end;
wenzelm@5828
   440
wenzelm@5828
   441
wenzelm@5828
   442
(* datatype transition *)
wenzelm@5828
   443
wenzelm@5828
   444
datatype transition = Transition of
wenzelm@16815
   445
 {name: string,                        (*command name*)
wenzelm@16815
   446
  pos: Position.T,                     (*source position*)
wenzelm@16815
   447
  source: OuterLex.token list option,  (*source text*)
wenzelm@16815
   448
  int_only: bool,                      (*interactive-only*)
wenzelm@16815
   449
  print: string list,                  (*print modes (union)*)
wenzelm@16815
   450
  no_timing: bool,                     (*suppress timing*)
wenzelm@16815
   451
  trans: trans list};                  (*primitive transitions (union)*)
wenzelm@5828
   452
wenzelm@14923
   453
fun make_transition (name, pos, source, int_only, print, no_timing, trans) =
wenzelm@14923
   454
  Transition {name = name, pos = pos, source = source,
wenzelm@14923
   455
    int_only = int_only, print = print, no_timing = no_timing, trans = trans};
wenzelm@5828
   456
wenzelm@14923
   457
fun map_transition f (Transition {name, pos, source, int_only, print, no_timing, trans}) =
wenzelm@14923
   458
  make_transition (f (name, pos, source, int_only, print, no_timing, trans));
wenzelm@5828
   459
wenzelm@16607
   460
val empty = make_transition ("<unknown>", Position.none, NONE, false, [], false, []);
wenzelm@14923
   461
wenzelm@14923
   462
fun name_of (Transition {name, ...}) = name;
wenzelm@14923
   463
fun source_of (Transition {source, ...}) = source;
wenzelm@5828
   464
wenzelm@5828
   465
wenzelm@5828
   466
(* diagnostics *)
wenzelm@5828
   467
wenzelm@5828
   468
fun str_of_transition (Transition {name, pos, ...}) = quote name ^ Position.str_of pos;
wenzelm@5828
   469
wenzelm@5828
   470
fun command_msg msg tr = msg ^ "command " ^ str_of_transition tr;
wenzelm@5828
   471
fun at_command tr = command_msg "At " tr ^ ".";
wenzelm@5828
   472
wenzelm@5828
   473
fun type_error tr state =
wenzelm@18685
   474
  ERROR (command_msg "Illegal application of " tr ^ " " ^ str_of_state state);
wenzelm@5828
   475
wenzelm@5828
   476
wenzelm@5828
   477
(* modify transitions *)
wenzelm@5828
   478
wenzelm@14923
   479
fun name nm = map_transition (fn (_, pos, source, int_only, print, no_timing, trans) =>
wenzelm@14923
   480
  (nm, pos, source, int_only, print, no_timing, trans));
wenzelm@5828
   481
wenzelm@14923
   482
fun position pos = map_transition (fn (name, _, source, int_only, print, no_timing, trans) =>
wenzelm@14923
   483
  (name, pos, source, int_only, print, no_timing, trans));
wenzelm@9010
   484
wenzelm@14923
   485
fun source src = map_transition (fn (name, pos, _, int_only, print, no_timing, trans) =>
skalberg@15531
   486
  (name, pos, SOME src, int_only, print, no_timing, trans));
wenzelm@5828
   487
wenzelm@14923
   488
fun interactive int_only = map_transition (fn (name, pos, source, _, print, no_timing, trans) =>
wenzelm@14923
   489
  (name, pos, source, int_only, print, no_timing, trans));
wenzelm@14923
   490
wenzelm@17363
   491
val no_timing = map_transition (fn (name, pos, source, int_only, print, _, trans) =>
wenzelm@17363
   492
  (name, pos, source, int_only, print, true, trans));
wenzelm@17363
   493
wenzelm@17363
   494
fun add_trans tr = map_transition (fn (name, pos, source, int_only, print, no_timing, trans) =>
wenzelm@17363
   495
  (name, pos, source, int_only, print, no_timing, trans @ [tr]));
wenzelm@17363
   496
wenzelm@16607
   497
fun print' mode = map_transition (fn (name, pos, source, int_only, print, no_timing, trans) =>
wenzelm@16607
   498
  (name, pos, source, int_only, insert (op =) mode print, no_timing, trans));
wenzelm@16607
   499
wenzelm@16607
   500
val print = print' "";
wenzelm@5828
   501
wenzelm@17363
   502
val three_buffersN = "three_buffers";
wenzelm@17363
   503
val print3 = print' three_buffersN;
wenzelm@5828
   504
wenzelm@5828
   505
wenzelm@21007
   506
(* basic transitions *)
wenzelm@5828
   507
wenzelm@22056
   508
fun init_theory f exit kill = add_trans (Init (f, (exit, kill)));
wenzelm@21958
   509
val init_empty = add_trans o InitEmpty;
wenzelm@6689
   510
val exit = add_trans Exit;
wenzelm@21958
   511
val undo_exit = add_trans UndoExit;
wenzelm@6689
   512
val kill = add_trans Kill;
wenzelm@20128
   513
val history = add_trans o History;
wenzelm@7612
   514
val keep' = add_trans o Keep;
wenzelm@18592
   515
fun map_current f = add_trans (Transaction (false, f));
wenzelm@18592
   516
fun app_current f = add_trans (Transaction (true, f));
wenzelm@5828
   517
wenzelm@7612
   518
fun keep f = add_trans (Keep (fn _ => f));
wenzelm@5828
   519
fun imperative f = keep (fn _ => f ());
wenzelm@5828
   520
wenzelm@21007
   521
val unknown_theory = imperative (fn () => warning "Unknown theory context");
wenzelm@21007
   522
val unknown_proof = imperative (fn () => warning "Unknown proof context");
wenzelm@21007
   523
val unknown_context = imperative (fn () => warning "Unknown context");
wenzelm@15668
   524
wenzelm@21007
   525
wenzelm@21007
   526
(* theory transitions *)
wenzelm@15668
   527
wenzelm@20963
   528
fun theory' f = app_current (fn int =>
wenzelm@20963
   529
  (fn Theory (Context.Theory thy, _) => Theory (Context.Theory (f int thy), NONE)
wenzelm@20963
   530
    | _ => raise UNDEF));
wenzelm@20963
   531
wenzelm@20963
   532
fun theory f = theory' (K f);
wenzelm@20963
   533
wenzelm@21294
   534
fun begin_local_theory begin f = app_current (fn _ =>
wenzelm@20963
   535
  (fn Theory (Context.Theory thy, _) =>
wenzelm@20963
   536
        let
wenzelm@20985
   537
          val lthy = f thy;
wenzelm@21294
   538
          val gthy = if begin then Context.Proof lthy else Context.Theory (loc_exit lthy);
wenzelm@21294
   539
        in Theory (gthy, SOME lthy) end
wenzelm@20963
   540
    | _ => raise UNDEF));
wenzelm@17076
   541
wenzelm@21294
   542
val end_local_theory = app_current (fn _ =>
wenzelm@21294
   543
  (fn Theory (Context.Proof lthy, _) => Theory (Context.Theory (loc_exit lthy), SOME lthy)
wenzelm@21007
   544
    | _ => raise UNDEF));
wenzelm@21007
   545
wenzelm@21007
   546
local
wenzelm@21007
   547
wenzelm@20963
   548
fun local_theory_presentation loc f g = app_current (fn int =>
wenzelm@21294
   549
  (fn Theory (gthy, _) =>
wenzelm@21294
   550
        let
wenzelm@21294
   551
          val finish = loc_finish loc gthy;
wenzelm@21294
   552
          val lthy' = f (loc_begin loc gthy);
wenzelm@21294
   553
        in Theory (finish lthy', SOME lthy') end
wenzelm@20963
   554
    | _ => raise UNDEF) #> tap (g int));
wenzelm@15668
   555
wenzelm@21007
   556
in
wenzelm@21007
   557
wenzelm@20963
   558
fun local_theory loc f = local_theory_presentation loc f (K I);
wenzelm@20963
   559
fun present_local_theory loc g = local_theory_presentation loc I g;
wenzelm@18955
   560
wenzelm@21007
   561
end;
wenzelm@21007
   562
wenzelm@21007
   563
wenzelm@21007
   564
(* proof transitions *)
wenzelm@21007
   565
wenzelm@21007
   566
fun end_proof f = map_current (fn int =>
wenzelm@21007
   567
  (fn Proof (prf, (finish, orig_gthy)) =>
wenzelm@21007
   568
        let val state = ProofHistory.current prf in
wenzelm@21007
   569
          if can (Proof.assert_bottom true) state then
wenzelm@21007
   570
            let
wenzelm@21007
   571
              val ctxt' = f int state;
wenzelm@21007
   572
              val gthy' = finish ctxt';
wenzelm@21007
   573
            in Theory (gthy', SOME ctxt') end
wenzelm@21007
   574
          else raise UNDEF
wenzelm@21007
   575
        end
wenzelm@21007
   576
    | SkipProof (h, (gthy, _)) =>
wenzelm@21007
   577
        if History.current h = 0 then Theory (gthy, NONE) else raise UNDEF
wenzelm@21007
   578
    | _ => raise UNDEF));
wenzelm@21007
   579
wenzelm@21294
   580
local
wenzelm@21294
   581
wenzelm@21294
   582
fun begin_proof init finish = app_current (fn int =>
wenzelm@21294
   583
  (fn Theory (gthy, _) =>
wenzelm@21294
   584
    let
berghofe@24453
   585
      val prf = init int gthy;
wenzelm@21294
   586
      val schematic = Proof.schematic_goal prf;
wenzelm@21294
   587
    in
wenzelm@21294
   588
      if ! skip_proofs andalso schematic then
wenzelm@21294
   589
        warning "Cannot skip proof of schematic goal statement"
wenzelm@21294
   590
      else ();
wenzelm@21294
   591
      if ! skip_proofs andalso not schematic then
wenzelm@21294
   592
        SkipProof
wenzelm@21294
   593
          (History.init (undo_limit int) 0, (finish gthy (Proof.global_skip_proof int prf), gthy))
wenzelm@21294
   594
      else Proof (ProofHistory.init (undo_limit int) prf, (finish gthy, gthy))
wenzelm@21294
   595
    end
wenzelm@21294
   596
  | _ => raise UNDEF));
wenzelm@21294
   597
wenzelm@21294
   598
in
wenzelm@21294
   599
berghofe@24453
   600
fun local_theory_to_proof' loc f = begin_proof (fn int => f int o loc_begin loc) (loc_finish loc);
berghofe@24453
   601
fun local_theory_to_proof loc f = local_theory_to_proof' loc (K f);
wenzelm@21294
   602
wenzelm@21294
   603
fun theory_to_proof f = begin_proof
berghofe@24453
   604
    (K (fn Context.Theory thy => f thy | _ => raise UNDEF))
wenzelm@21294
   605
    (K (Context.Theory o ProofContext.theory_of));
wenzelm@21294
   606
wenzelm@21294
   607
end;
wenzelm@21294
   608
wenzelm@21007
   609
val forget_proof = map_current (fn _ =>
wenzelm@21007
   610
  (fn Proof (_, (_, orig_gthy)) => Theory (orig_gthy, NONE)
wenzelm@21007
   611
    | SkipProof (_, (_, orig_gthy)) => Theory (orig_gthy, NONE)
wenzelm@21007
   612
    | _ => raise UNDEF));
wenzelm@21007
   613
wenzelm@21177
   614
fun present_proof f = map_current (fn int =>
wenzelm@21177
   615
  (fn Proof (prf, x) => Proof (ProofHistory.apply I prf, x)
wenzelm@21177
   616
    | SkipProof (h, x) => SkipProof (History.apply I h, x)
wenzelm@21177
   617
    | _ => raise UNDEF) #> tap (f int));
wenzelm@21177
   618
wenzelm@17904
   619
fun proofs' f = map_current (fn int =>
wenzelm@21007
   620
  (fn Proof (prf, x) => Proof (ProofHistory.applys (f int) prf, x)
wenzelm@21007
   621
    | SkipProof (h, x) => SkipProof (History.apply I h, x)
wenzelm@16815
   622
    | _ => raise UNDEF));
wenzelm@15668
   623
wenzelm@17904
   624
fun proof' f = proofs' (Seq.single oo f);
wenzelm@17904
   625
val proofs = proofs' o K;
wenzelm@6689
   626
val proof = proof' o K;
wenzelm@16815
   627
wenzelm@16815
   628
fun actual_proof f = map_current (fn _ =>
wenzelm@21007
   629
  (fn Proof (prf, x) => Proof (f prf, x)
wenzelm@20963
   630
    | _ => raise UNDEF));
wenzelm@16815
   631
wenzelm@16815
   632
fun skip_proof f = map_current (fn _ =>
wenzelm@21007
   633
  (fn SkipProof (h, x) => SkipProof (f h, x)
wenzelm@18563
   634
    | _ => raise UNDEF));
wenzelm@18563
   635
wenzelm@16815
   636
fun skip_proof_to_theory p = map_current (fn _ =>
wenzelm@21007
   637
  (fn SkipProof (h, (gthy, _)) =>
wenzelm@21007
   638
    if p (History.current h) then Theory (gthy, NONE)
wenzelm@17904
   639
    else raise UNDEF
wenzelm@17904
   640
  | _ => raise UNDEF));
wenzelm@5828
   641
wenzelm@5828
   642
wenzelm@5828
   643
wenzelm@5828
   644
(** toplevel transactions **)
wenzelm@5828
   645
wenzelm@5828
   646
(* apply transitions *)
wenzelm@5828
   647
wenzelm@6664
   648
local
wenzelm@6664
   649
wenzelm@23363
   650
fun app int (tr as Transition {trans, pos, int_only, print, no_timing, ...}) state =
wenzelm@5828
   651
  let
wenzelm@21962
   652
    val _ =
wenzelm@21962
   653
      if not int andalso int_only then warning (command_msg "Interactive-only " tr)
wenzelm@21962
   654
      else ();
wenzelm@16682
   655
wenzelm@22588
   656
    fun do_timing f x = (warning (command_msg "" tr); timeap f x);
wenzelm@16682
   657
    fun do_profiling f x = profile (! profiling) f x;
wenzelm@16682
   658
wenzelm@6689
   659
    val (result, opt_exn) =
wenzelm@23363
   660
       state |> (apply_trans int pos trans
wenzelm@23428
   661
        |> (if ! profiling > 0 andalso not no_timing then do_profiling else I)
wenzelm@16729
   662
        |> (if ! profiling > 0 orelse ! timing andalso not no_timing then do_timing else I));
wenzelm@21962
   663
    val _ =
wenzelm@21962
   664
      if int andalso not (! quiet) andalso exists (member (op =) print) ("" :: ! print_mode)
wenzelm@21962
   665
      then print_state false result else ();
skalberg@15570
   666
  in (result, Option.map (fn UNDEF => type_error tr state | exn => exn) opt_exn) end;
wenzelm@6664
   667
wenzelm@6664
   668
in
wenzelm@5828
   669
wenzelm@6689
   670
fun apply int tr st =
wenzelm@6965
   671
  (case app int tr st of
skalberg@15531
   672
    (_, SOME TERMINATE) => NONE
skalberg@15531
   673
  | (_, SOME RESTART) => SOME (toplevel, NONE)
skalberg@15531
   674
  | (state', SOME (EXCURSION_FAIL exn_info)) => SOME (state', SOME exn_info)
skalberg@15531
   675
  | (state', SOME exn) => SOME (state', SOME (exn, at_command tr))
skalberg@15531
   676
  | (state', NONE) => SOME (state', NONE));
wenzelm@6664
   677
wenzelm@6664
   678
end;
wenzelm@5828
   679
wenzelm@5828
   680
wenzelm@17076
   681
(* excursion: toplevel -- apply transformers/presentation -- toplevel *)
wenzelm@5828
   682
wenzelm@6664
   683
local
wenzelm@6664
   684
wenzelm@5828
   685
fun excur [] x = x
wenzelm@17076
   686
  | excur ((tr, pr) :: trs) (st, res) =
wenzelm@17321
   687
      (case apply (! interact) tr st of
skalberg@15531
   688
        SOME (st', NONE) =>
wenzelm@18685
   689
          excur trs (st', pr st st' res handle exn =>
wenzelm@10324
   690
            raise EXCURSION_FAIL (exn, "Presentation failed\n" ^ at_command tr))
skalberg@15531
   691
      | SOME (st', SOME exn_info) => raise EXCURSION_FAIL exn_info
skalberg@15531
   692
      | NONE => raise EXCURSION_FAIL (TERMINATE, at_command tr));
wenzelm@5828
   693
wenzelm@17076
   694
fun no_pr _ _ _ = ();
wenzelm@17076
   695
wenzelm@6664
   696
in
wenzelm@6664
   697
wenzelm@17076
   698
fun present_excursion trs res =
wenzelm@21958
   699
  (case excur trs (toplevel, res) of
wenzelm@22056
   700
    (state as Toplevel _, res') => (safe_exit state; res')
wenzelm@18685
   701
  | _ => error "Unfinished development at end of input")
wenzelm@9134
   702
  handle exn => error (exn_message exn);
wenzelm@9134
   703
wenzelm@17076
   704
fun excursion trs = present_excursion (map (rpair no_pr) trs) ();
wenzelm@7062
   705
wenzelm@6664
   706
end;
wenzelm@6664
   707
wenzelm@5828
   708
wenzelm@5828
   709
wenzelm@5828
   710
(** interactive transformations **)
wenzelm@5828
   711
wenzelm@5828
   712
(* the global state reference *)
wenzelm@5828
   713
skalberg@15531
   714
val global_state = ref (toplevel, NONE: (exn * string) option);
wenzelm@5828
   715
skalberg@15531
   716
fun set_state state = global_state := (state, NONE);
wenzelm@5828
   717
fun get_state () = fst (! global_state);
wenzelm@5828
   718
fun exn () = snd (! global_state);
wenzelm@5828
   719
wenzelm@5828
   720
wenzelm@24295
   721
(* apply transformers to global state --- NOT THREAD-SAFE! *)
wenzelm@5828
   722
wenzelm@14985
   723
nonfix >> >>>;
wenzelm@5828
   724
wenzelm@24295
   725
fun >> tr =
wenzelm@5828
   726
  (case apply true tr (get_state ()) of
skalberg@15531
   727
    NONE => false
skalberg@15531
   728
  | SOME (state', exn_info) =>
wenzelm@5828
   729
      (global_state := (state', exn_info);
wenzelm@22014
   730
        print_exn exn_info;
wenzelm@24295
   731
        true));
wenzelm@5828
   732
wenzelm@14985
   733
fun >>> [] = ()
wenzelm@14985
   734
  | >>> (tr :: trs) = if >> tr then >>> trs else ();
wenzelm@14985
   735
wenzelm@21958
   736
fun init_state () = (>> (init_empty (K ()) empty); ());
wenzelm@21958
   737
wenzelm@21958
   738
wenzelm@21958
   739
(* the Isar source of transitions *)
wenzelm@21958
   740
wenzelm@21958
   741
type 'a isar =
wenzelm@21958
   742
  (transition, (transition option,
wenzelm@21958
   743
    (OuterLex.token, (OuterLex.token option, (OuterLex.token, (OuterLex.token,
wenzelm@21958
   744
      Position.T * (Symbol.symbol, (string, 'a) Source.source) Source.source)
wenzelm@21958
   745
          Source.source) Source.source) Source.source) Source.source) Source.source) Source.source;
wenzelm@21958
   746
wenzelm@17513
   747
(*Spurious interrupts ahead!  Race condition?*)
wenzelm@17513
   748
fun get_interrupt src = SOME (Source.get_single src) handle Interrupt => NONE;
wenzelm@7602
   749
wenzelm@20928
   750
fun warn_secure () =
wenzelm@20928
   751
  let val secure = Secure.is_secure ()
wenzelm@20928
   752
  in if secure then warning "Cannot exit to ML in secure mode" else (); secure end;
wenzelm@20928
   753
wenzelm@5828
   754
fun raw_loop src =
wenzelm@23720
   755
  let val prompt = Output.escape (Markup.enclose Markup.prompt Source.default_prompt) in
wenzelm@23640
   756
    (case get_interrupt (Source.set_prompt prompt src) of
wenzelm@23640
   757
      NONE => (writeln "\nInterrupt."; raw_loop src)
wenzelm@23640
   758
    | SOME NONE => if warn_secure () then quit () else ()
wenzelm@23640
   759
    | SOME (SOME (tr, src')) =>
wenzelm@23640
   760
        if >> tr orelse warn_secure () then raw_loop src'
wenzelm@23640
   761
        else ())
wenzelm@23640
   762
  end;
wenzelm@5828
   763
wenzelm@12987
   764
fun loop src = ignore_interrupt raw_loop src;
wenzelm@5828
   765
wenzelm@5828
   766
end;