src/Pure/Isar/toplevel.ML
author wenzelm
Fri Nov 10 22:18:54 2006 +0100 (2006-11-10)
changeset 21294 5cd48242ef17
parent 21277 ac2d7e03a3b1
child 21310 bfcc24fc7c46
permissions -rw-r--r--
simplified local theory wrappers;
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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 toplevel: 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 assert: bool -> unit
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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 -> Context.generic
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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 prompt_state_default: state -> string
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  val prompt_state_fn: (state -> string) ref
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  val print_state_context: state -> unit
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  val print_state_default: bool -> state -> unit
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  val print_state_fn: (bool -> state -> unit) ref
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  val print_state: bool -> state -> unit
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  val pretty_state: bool -> state -> Pretty.T list
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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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  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 reset: transition -> transition
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  val init: (bool -> node) -> (node -> unit) -> (node -> unit) -> transition -> transition
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  val 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 init_theory: (bool -> theory) -> (theory -> unit) -> (theory -> unit) ->
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    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 -> (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 apply: bool -> transition -> state -> (state * (exn * string) option) option
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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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  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 state *)
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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 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 = State of (node History.T * ((node -> unit) * (node -> unit))) option;
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val toplevel = State NONE;
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fun is_toplevel (State NONE) = true
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  | is_toplevel _ = false;
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fun level (State NONE) = 0
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  | level (State (SOME (node, _))) =
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      (case History.current node of
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        Theory (Context.Theory _, _) => 0
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      | Theory (Context.Proof _, _) => 1
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      | Proof (prf, _) => Proof.level (ProofHistory.current prf) + 1
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      | SkipProof (h, _) => History.current h + 2);   (*different notion of proof depth!*)
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fun str_of_state (State NONE) = "at top level"
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  | str_of_state (State (SOME (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 assert true = ()
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  | assert false = raise UNDEF;
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fun node_history_of (State NONE) = raise UNDEF
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  | node_history_of (State (SOME (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 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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(* prompt state *)
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fun prompt_state_default (State _) = Source.default_prompt;
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val prompt_state_fn = ref prompt_state_default;
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fun prompt_state state = ! prompt_state_fn state;
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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 pretty_state_context state =
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  (case try context_of state of NONE => []
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  | SOME gthy => pretty_context gthy);
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fun pretty_node prf_only (Theory (gthy, _)) = if prf_only then [] else pretty_context gthy
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  | pretty_node _ (Proof (prf, _)) =
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      Proof.pretty_state (ProofHistory.position prf) (ProofHistory.current prf)
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  | pretty_node _ (SkipProof (h, _)) =
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      [Pretty.str ("skipped proof: depth " ^ string_of_int (History.current h))];
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fun pretty_state prf_only state =
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  let val ref (begin_state, end_state, _) = Display.current_goals_markers in
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    (case try node_of state of NONE => []
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    | SOME node =>
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        (if begin_state = "" then [] else [Pretty.str begin_state]) @
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        pretty_node prf_only node @
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        (if end_state = "" then [] else [Pretty.str end_state]))
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  end;
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val print_state_context = Pretty.writelns o pretty_state_context;
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fun print_state_default prf_only state = Pretty.writelns (pretty_state prf_only state);
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val print_state_fn = ref print_state_default;
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fun print_state prf_only state = ! print_state_fn prf_only state;
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(** toplevel transitions **)
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val quiet = ref false;
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val debug = ref false;
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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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(* print exceptions *)
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local
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fun with_context f xs =
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  (case Context.get_context () of NONE => []
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  | SOME thy => map (f thy) 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 _ Output.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 (EXCEPTION (exn, msg)) = cat_lines [exn_msg detailed exn, 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 detailed (MetaSimplifier.SIMPROC_FAIL (name, exn)) =
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      fail_msg detailed "simproc" ((name, Position.none), exn)
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  | exn_msg detailed (Attrib.ATTRIB_FAIL info) = fail_msg detailed "attribute" info
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  | exn_msg detailed (Method.METHOD_FAIL info) = fail_msg detailed "method" info
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  | exn_msg detailed (Antiquote.ANTIQUOTE_FAIL info) = fail_msg detailed "antiquotation" info
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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 Sign.string_of_typ Ts @ with_context Sign.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)) = raised "TERM" (msg :: with_context Sign.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 :: map Display.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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and fail_msg detailed kind ((name, pos), exn) =
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  "Error in " ^ kind ^ " " ^ quote name ^ Position.str_of pos ^ ":\n" ^ exn_msg detailed 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
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    setmp Library.do_transform_failure false
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      exception_trace (fn () => f x)
wenzelm@18685
   324
  else f x;
wenzelm@18685
   325
wenzelm@20128
   326
fun interruptible f x =
wenzelm@20128
   327
  let val y = ref x
wenzelm@20128
   328
  in raise_interrupt (fn () => y := f x) (); ! y end;
wenzelm@20128
   329
wenzelm@20128
   330
in
wenzelm@20128
   331
wenzelm@20128
   332
fun controlled_execution f =
wenzelm@20128
   333
  f
wenzelm@20128
   334
  |> debugging
wenzelm@20128
   335
  |> interruptible
wenzelm@20128
   336
  |> setmp Output.do_toplevel_errors false;
wenzelm@20128
   337
wenzelm@20128
   338
fun program f =
wenzelm@20128
   339
  Output.ML_errors (fn () => debugging f () handle exn => error (exn_message exn)) ();
wenzelm@20128
   340
wenzelm@20128
   341
end;
wenzelm@20128
   342
wenzelm@5828
   343
wenzelm@16815
   344
(* node transactions and recovery from stale theories *)
wenzelm@6689
   345
wenzelm@16815
   346
(*NB: proof commands should be non-destructive!*)
wenzelm@7022
   347
wenzelm@6689
   348
local
wenzelm@6689
   349
wenzelm@16452
   350
fun is_stale state = Context.is_stale (theory_of state) handle UNDEF => false;
wenzelm@6689
   351
wenzelm@18685
   352
val stale_theory = ERROR "Stale theory encountered after succesful execution!";
wenzelm@16815
   353
wenzelm@21177
   354
fun map_theory f = History.map
wenzelm@21177
   355
  (fn Theory (gthy, _) => Theory (Context.mapping f (LocalTheory.raw_theory f) gthy, NONE)
wenzelm@21177
   356
    | node => node);
wenzelm@6689
   357
skalberg@15531
   358
fun return (result, NONE) = result
skalberg@15531
   359
  | return (result, SOME exn) = raise FAILURE (result, exn);
wenzelm@7022
   360
wenzelm@6689
   361
in
wenzelm@6689
   362
wenzelm@20128
   363
fun transaction hist f (node, term) =
wenzelm@20128
   364
  let
wenzelm@21177
   365
    val cont_node = map_theory Theory.checkpoint node;
wenzelm@21177
   366
    val back_node = map_theory Theory.copy cont_node;
wenzelm@20128
   367
    fun state nd = State (SOME (nd, term));
wenzelm@20128
   368
    fun normal_state nd = (state nd, NONE);
wenzelm@20128
   369
    fun error_state nd exn = (state nd, SOME exn);
wenzelm@6689
   370
wenzelm@20128
   371
    val (result, err) =
wenzelm@20128
   372
      cont_node
wenzelm@20128
   373
      |> (f
wenzelm@21177
   374
          |> (if hist then History.apply' (History.current back_node) else History.map)
wenzelm@20128
   375
          |> controlled_execution)
wenzelm@20128
   376
      |> normal_state
wenzelm@20128
   377
      handle exn => error_state cont_node exn;
wenzelm@20128
   378
  in
wenzelm@20128
   379
    if is_stale result
wenzelm@20128
   380
    then return (error_state back_node (the_default stale_theory err))
wenzelm@20128
   381
    else return (result, err)
wenzelm@20128
   382
  end;
wenzelm@6689
   383
wenzelm@6689
   384
end;
wenzelm@6689
   385
wenzelm@6689
   386
wenzelm@6689
   387
(* primitive transitions *)
wenzelm@6689
   388
wenzelm@18563
   389
(*Note: Recovery from stale theories is provided only for theory-level
wenzelm@18589
   390
  operations via Transaction.  Other node or state operations should
wenzelm@18589
   391
  not touch theories at all.  Interrupts are enabled only for Keep and
wenzelm@18589
   392
  Transaction.*)
wenzelm@5828
   393
wenzelm@5828
   394
datatype trans =
wenzelm@18563
   395
  Reset |                                               (*empty toplevel*)
wenzelm@8465
   396
  Init of (bool -> node) * ((node -> unit) * (node -> unit)) |
wenzelm@18563
   397
                                                        (*init node; with exit/kill operation*)
wenzelm@18563
   398
  Exit |                                                (*conclude node*)
wenzelm@18563
   399
  Kill |                                                (*abort node*)
wenzelm@20128
   400
  History of node History.T -> node History.T |         (*history operation (undo etc.)*)
wenzelm@18563
   401
  Keep of bool -> state -> unit |                       (*peek at state*)
wenzelm@18592
   402
  Transaction of bool * (bool -> node -> node);         (*node transaction*)
wenzelm@6689
   403
skalberg@15531
   404
fun undo_limit int = if int then NONE else SOME 0;
wenzelm@6689
   405
wenzelm@6689
   406
local
wenzelm@5828
   407
wenzelm@6689
   408
fun apply_tr _ Reset _ = toplevel
skalberg@15531
   409
  | apply_tr int (Init (f, term)) (State NONE) =
skalberg@15531
   410
      State (SOME (History.init (undo_limit int) (f int), term))
skalberg@15531
   411
  | apply_tr _ (Init _ ) (State (SOME _)) = raise UNDEF
skalberg@15531
   412
  | apply_tr _ Exit (State NONE) = raise UNDEF
skalberg@15531
   413
  | apply_tr _ Exit (State (SOME (node, (exit, _)))) =
skalberg@15531
   414
      (exit (History.current node); State NONE)
skalberg@15531
   415
  | apply_tr _ Kill (State NONE) = raise UNDEF
skalberg@15531
   416
  | apply_tr _ Kill (State (SOME (node, (_, kill)))) =
skalberg@15531
   417
      (kill (History.current node); State NONE)
skalberg@15531
   418
  | apply_tr _ (History _) (State NONE) = raise UNDEF
skalberg@15531
   419
  | apply_tr _ (History f) (State (SOME (node, term))) = State (SOME (f node, term))
wenzelm@20128
   420
  | apply_tr int (Keep f) state =
wenzelm@20128
   421
      controlled_execution (fn x => tap (f int) x) state
wenzelm@20128
   422
  | apply_tr _ (Transaction _) (State NONE) = raise UNDEF
wenzelm@20128
   423
  | apply_tr int (Transaction (hist, f)) (State (SOME state)) =
wenzelm@20128
   424
      transaction hist (fn x => f int x) state;
wenzelm@5828
   425
wenzelm@6689
   426
fun apply_union _ [] state = raise FAILURE (state, UNDEF)
wenzelm@6689
   427
  | apply_union int (tr :: trs) state =
wenzelm@18685
   428
      apply_tr int tr state
wenzelm@6689
   429
        handle UNDEF => apply_union int trs state
wenzelm@6689
   430
          | FAILURE (alt_state, UNDEF) => apply_union int 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
skalberg@15531
   436
fun apply_trans int trs state = (apply_union int 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@5828
   508
val reset = add_trans Reset;
wenzelm@6689
   509
fun init f exit kill = add_trans (Init (f, (exit, kill)));
wenzelm@6689
   510
val exit = add_trans Exit;
wenzelm@6689
   511
val kill = add_trans Kill;
wenzelm@20128
   512
val history = add_trans o History;
wenzelm@7612
   513
val keep' = add_trans o Keep;
wenzelm@18592
   514
fun map_current f = add_trans (Transaction (false, f));
wenzelm@18592
   515
fun app_current f = add_trans (Transaction (true, f));
wenzelm@5828
   516
wenzelm@7612
   517
fun keep f = add_trans (Keep (fn _ => f));
wenzelm@5828
   518
fun imperative f = keep (fn _ => f ());
wenzelm@5828
   519
wenzelm@6689
   520
fun init_theory f exit kill =
wenzelm@20963
   521
  init (fn int => Theory (Context.Theory (f int), NONE))
wenzelm@20963
   522
    (fn Theory (Context.Theory thy, _) => exit thy | _ => raise UNDEF)
wenzelm@20963
   523
    (fn Theory (Context.Theory thy, _) => kill thy | _ => raise UNDEF);
wenzelm@5828
   524
wenzelm@21007
   525
val unknown_theory = imperative (fn () => warning "Unknown theory context");
wenzelm@21007
   526
val unknown_proof = imperative (fn () => warning "Unknown proof context");
wenzelm@21007
   527
val unknown_context = imperative (fn () => warning "Unknown context");
wenzelm@15668
   528
wenzelm@21007
   529
wenzelm@21007
   530
(* theory transitions *)
wenzelm@15668
   531
wenzelm@20963
   532
fun theory' f = app_current (fn int =>
wenzelm@20963
   533
  (fn Theory (Context.Theory thy, _) => Theory (Context.Theory (f int thy), NONE)
wenzelm@20963
   534
    | _ => raise UNDEF));
wenzelm@20963
   535
wenzelm@20963
   536
fun theory f = theory' (K f);
wenzelm@20963
   537
wenzelm@21294
   538
fun begin_local_theory begin f = app_current (fn _ =>
wenzelm@20963
   539
  (fn Theory (Context.Theory thy, _) =>
wenzelm@20963
   540
        let
wenzelm@20985
   541
          val lthy = f thy;
wenzelm@21294
   542
          val gthy = if begin then Context.Proof lthy else Context.Theory (loc_exit lthy);
wenzelm@21294
   543
        in Theory (gthy, SOME lthy) end
wenzelm@20963
   544
    | _ => raise UNDEF));
wenzelm@17076
   545
wenzelm@21294
   546
val end_local_theory = app_current (fn _ =>
wenzelm@21294
   547
  (fn Theory (Context.Proof lthy, _) => Theory (Context.Theory (loc_exit lthy), SOME lthy)
wenzelm@21007
   548
    | _ => raise UNDEF));
wenzelm@21007
   549
wenzelm@21007
   550
local
wenzelm@21007
   551
wenzelm@20963
   552
fun local_theory_presentation loc f g = app_current (fn int =>
wenzelm@21294
   553
  (fn Theory (gthy, _) =>
wenzelm@21294
   554
        let
wenzelm@21294
   555
          val finish = loc_finish loc gthy;
wenzelm@21294
   556
          val lthy' = f (loc_begin loc gthy);
wenzelm@21294
   557
        in Theory (finish lthy', SOME lthy') end
wenzelm@20963
   558
    | _ => raise UNDEF) #> tap (g int));
wenzelm@15668
   559
wenzelm@21007
   560
in
wenzelm@21007
   561
wenzelm@20963
   562
fun local_theory loc f = local_theory_presentation loc f (K I);
wenzelm@20963
   563
fun present_local_theory loc g = local_theory_presentation loc I g;
wenzelm@18955
   564
wenzelm@21007
   565
end;
wenzelm@21007
   566
wenzelm@21007
   567
wenzelm@21007
   568
(* proof transitions *)
wenzelm@21007
   569
wenzelm@21007
   570
fun end_proof f = map_current (fn int =>
wenzelm@21007
   571
  (fn Proof (prf, (finish, orig_gthy)) =>
wenzelm@21007
   572
        let val state = ProofHistory.current prf in
wenzelm@21007
   573
          if can (Proof.assert_bottom true) state then
wenzelm@21007
   574
            let
wenzelm@21007
   575
              val ctxt' = f int state;
wenzelm@21007
   576
              val gthy' = finish ctxt';
wenzelm@21007
   577
            in Theory (gthy', SOME ctxt') end
wenzelm@21007
   578
          else raise UNDEF
wenzelm@21007
   579
        end
wenzelm@21007
   580
    | SkipProof (h, (gthy, _)) =>
wenzelm@21007
   581
        if History.current h = 0 then Theory (gthy, NONE) else raise UNDEF
wenzelm@21007
   582
    | _ => raise UNDEF));
wenzelm@21007
   583
wenzelm@21294
   584
local
wenzelm@21294
   585
wenzelm@21294
   586
fun begin_proof init finish = app_current (fn int =>
wenzelm@21294
   587
  (fn Theory (gthy, _) =>
wenzelm@21294
   588
    let
wenzelm@21294
   589
      val prf = init gthy;
wenzelm@21294
   590
      val schematic = Proof.schematic_goal prf;
wenzelm@21294
   591
    in
wenzelm@21294
   592
      if ! skip_proofs andalso schematic then
wenzelm@21294
   593
        warning "Cannot skip proof of schematic goal statement"
wenzelm@21294
   594
      else ();
wenzelm@21294
   595
      if ! skip_proofs andalso not schematic then
wenzelm@21294
   596
        SkipProof
wenzelm@21294
   597
          (History.init (undo_limit int) 0, (finish gthy (Proof.global_skip_proof int prf), gthy))
wenzelm@21294
   598
      else Proof (ProofHistory.init (undo_limit int) prf, (finish gthy, gthy))
wenzelm@21294
   599
    end
wenzelm@21294
   600
  | _ => raise UNDEF));
wenzelm@21294
   601
wenzelm@21294
   602
in
wenzelm@21294
   603
wenzelm@21294
   604
fun local_theory_to_proof loc f = begin_proof (f o loc_begin loc) (loc_finish loc);
wenzelm@21294
   605
wenzelm@21294
   606
fun theory_to_proof f = begin_proof
wenzelm@21294
   607
    (fn Context.Theory thy => f thy | _ => raise UNDEF)
wenzelm@21294
   608
    (K (Context.Theory o ProofContext.theory_of));
wenzelm@21294
   609
wenzelm@21294
   610
end;
wenzelm@21294
   611
wenzelm@21007
   612
val forget_proof = map_current (fn _ =>
wenzelm@21007
   613
  (fn Proof (_, (_, orig_gthy)) => Theory (orig_gthy, NONE)
wenzelm@21007
   614
    | SkipProof (_, (_, orig_gthy)) => Theory (orig_gthy, NONE)
wenzelm@21007
   615
    | _ => raise UNDEF));
wenzelm@21007
   616
wenzelm@21177
   617
fun present_proof f = map_current (fn int =>
wenzelm@21177
   618
  (fn Proof (prf, x) => Proof (ProofHistory.apply I prf, x)
wenzelm@21177
   619
    | SkipProof (h, x) => SkipProof (History.apply I h, x)
wenzelm@21177
   620
    | _ => raise UNDEF) #> tap (f int));
wenzelm@21177
   621
wenzelm@17904
   622
fun proofs' f = map_current (fn int =>
wenzelm@21007
   623
  (fn Proof (prf, x) => Proof (ProofHistory.applys (f int) prf, x)
wenzelm@21007
   624
    | SkipProof (h, x) => SkipProof (History.apply I h, x)
wenzelm@16815
   625
    | _ => raise UNDEF));
wenzelm@15668
   626
wenzelm@17904
   627
fun proof' f = proofs' (Seq.single oo f);
wenzelm@17904
   628
val proofs = proofs' o K;
wenzelm@6689
   629
val proof = proof' o K;
wenzelm@16815
   630
wenzelm@16815
   631
fun actual_proof f = map_current (fn _ =>
wenzelm@21007
   632
  (fn Proof (prf, x) => Proof (f prf, x)
wenzelm@20963
   633
    | _ => raise UNDEF));
wenzelm@16815
   634
wenzelm@16815
   635
fun skip_proof f = map_current (fn _ =>
wenzelm@21007
   636
  (fn SkipProof (h, x) => SkipProof (f h, x)
wenzelm@18563
   637
    | _ => raise UNDEF));
wenzelm@18563
   638
wenzelm@16815
   639
fun skip_proof_to_theory p = map_current (fn _ =>
wenzelm@21007
   640
  (fn SkipProof (h, (gthy, _)) =>
wenzelm@21007
   641
    if p (History.current h) then Theory (gthy, NONE)
wenzelm@17904
   642
    else raise UNDEF
wenzelm@17904
   643
  | _ => raise UNDEF));
wenzelm@5828
   644
wenzelm@5828
   645
wenzelm@5828
   646
wenzelm@5828
   647
(** toplevel transactions **)
wenzelm@5828
   648
wenzelm@5828
   649
(* apply transitions *)
wenzelm@5828
   650
wenzelm@6664
   651
local
wenzelm@6664
   652
wenzelm@9010
   653
fun app int (tr as Transition {trans, int_only, print, no_timing, ...}) state =
wenzelm@5828
   654
  let
wenzelm@16682
   655
    val _ = conditional (not int andalso int_only) (fn () =>
wenzelm@16682
   656
      warning (command_msg "Interactive-only " tr));
wenzelm@16682
   657
wenzelm@18685
   658
    fun do_timing f x = (Output.info (command_msg "" tr); timeap f x);
wenzelm@16682
   659
    fun do_profiling f x = profile (! profiling) f x;
wenzelm@16682
   660
wenzelm@6689
   661
    val (result, opt_exn) =
wenzelm@16729
   662
       state |> (apply_trans int trans
wenzelm@16729
   663
        |> (if ! profiling > 0 then do_profiling else I)
wenzelm@16729
   664
        |> (if ! profiling > 0 orelse ! timing andalso not no_timing then do_timing else I));
wenzelm@16607
   665
    val _ = conditional (int andalso not (! quiet) andalso
wenzelm@20664
   666
        exists (member (op =) print) ("" :: ! print_mode))
wenzelm@16607
   667
      (fn () => print_state false result);
skalberg@15570
   668
  in (result, Option.map (fn UNDEF => type_error tr state | exn => exn) opt_exn) end;
wenzelm@6664
   669
wenzelm@6664
   670
in
wenzelm@5828
   671
wenzelm@6689
   672
fun apply int tr st =
wenzelm@6965
   673
  (case app int tr st of
skalberg@15531
   674
    (_, SOME TERMINATE) => NONE
skalberg@15531
   675
  | (_, SOME RESTART) => SOME (toplevel, NONE)
skalberg@15531
   676
  | (state', SOME (EXCURSION_FAIL exn_info)) => SOME (state', SOME exn_info)
skalberg@15531
   677
  | (state', SOME exn) => SOME (state', SOME (exn, at_command tr))
skalberg@15531
   678
  | (state', NONE) => SOME (state', NONE));
wenzelm@6664
   679
wenzelm@6664
   680
end;
wenzelm@5828
   681
wenzelm@5828
   682
wenzelm@17076
   683
(* excursion: toplevel -- apply transformers/presentation -- toplevel *)
wenzelm@5828
   684
wenzelm@6664
   685
local
wenzelm@6664
   686
wenzelm@5828
   687
fun excur [] x = x
wenzelm@17076
   688
  | excur ((tr, pr) :: trs) (st, res) =
wenzelm@17321
   689
      (case apply (! interact) tr st of
skalberg@15531
   690
        SOME (st', NONE) =>
wenzelm@18685
   691
          excur trs (st', pr st st' res handle exn =>
wenzelm@10324
   692
            raise EXCURSION_FAIL (exn, "Presentation failed\n" ^ at_command tr))
skalberg@15531
   693
      | SOME (st', SOME exn_info) => raise EXCURSION_FAIL exn_info
skalberg@15531
   694
      | NONE => raise EXCURSION_FAIL (TERMINATE, at_command tr));
wenzelm@5828
   695
wenzelm@17076
   696
fun no_pr _ _ _ = ();
wenzelm@17076
   697
wenzelm@6664
   698
in
wenzelm@6664
   699
wenzelm@17076
   700
fun present_excursion trs res =
skalberg@15531
   701
  (case excur trs (State NONE, res) of
skalberg@15531
   702
    (State NONE, res') => res'
wenzelm@18685
   703
  | _ => error "Unfinished development at end of input")
wenzelm@9134
   704
  handle exn => error (exn_message exn);
wenzelm@9134
   705
wenzelm@17076
   706
fun excursion trs = present_excursion (map (rpair no_pr) trs) ();
wenzelm@7062
   707
wenzelm@6664
   708
end;
wenzelm@6664
   709
wenzelm@5828
   710
wenzelm@5828
   711
wenzelm@5828
   712
(** interactive transformations **)
wenzelm@5828
   713
wenzelm@5828
   714
(* the global state reference *)
wenzelm@5828
   715
skalberg@15531
   716
val global_state = ref (toplevel, NONE: (exn * string) option);
wenzelm@5828
   717
skalberg@15531
   718
fun set_state state = global_state := (state, NONE);
wenzelm@5828
   719
fun get_state () = fst (! global_state);
wenzelm@5828
   720
fun exn () = snd (! global_state);
wenzelm@5828
   721
wenzelm@5828
   722
wenzelm@6965
   723
(* the Isar source of transitions *)
wenzelm@6965
   724
nipkow@14091
   725
type 'a isar =
wenzelm@6965
   726
  (transition, (transition option,
wenzelm@12881
   727
    (OuterLex.token, (OuterLex.token option, (OuterLex.token, (OuterLex.token,
nipkow@14091
   728
      Position.T * (Symbol.symbol, (string, 'a) Source.source) Source.source)
wenzelm@12881
   729
          Source.source) Source.source) Source.source) Source.source) Source.source) Source.source;
wenzelm@6965
   730
wenzelm@6965
   731
wenzelm@5828
   732
(* apply transformers to global state *)
wenzelm@5828
   733
wenzelm@14985
   734
nonfix >> >>>;
wenzelm@5828
   735
wenzelm@5828
   736
fun >> tr =
wenzelm@5828
   737
  (case apply true tr (get_state ()) of
skalberg@15531
   738
    NONE => false
skalberg@15531
   739
  | SOME (state', exn_info) =>
wenzelm@5828
   740
      (global_state := (state', exn_info);
wenzelm@16729
   741
        print_exn exn_info;
wenzelm@5828
   742
        true));
wenzelm@5828
   743
wenzelm@14985
   744
fun >>> [] = ()
wenzelm@14985
   745
  | >>> (tr :: trs) = if >> tr then >>> trs else ();
wenzelm@14985
   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@7602
   755
  (case get_interrupt (Source.set_prompt (prompt_state (get_state ())) src) of
skalberg@15531
   756
    NONE => (writeln "\nInterrupt."; raw_loop src)
wenzelm@20928
   757
  | SOME NONE => if warn_secure () then quit () else ()
wenzelm@20928
   758
  | SOME (SOME (tr, src')) =>
wenzelm@20928
   759
      if >> tr orelse warn_secure () then raw_loop src'
wenzelm@20928
   760
      else ());
wenzelm@5828
   761
wenzelm@12987
   762
fun loop src = ignore_interrupt raw_loop src;
wenzelm@5828
   763
wenzelm@5828
   764
end;