src/Pure/Isar/toplevel.ML
author haftmann
Fri Nov 10 07:44:47 2006 +0100 (2006-11-10)
changeset 21286 b5e7b80caa6a
parent 21277 ac2d7e03a3b1
child 21294 5cd48242ef17
permissions -rw-r--r--
introduces canonical AList functions for loop_tacs
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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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(* datatype state *)
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type generic_theory = Context.generic;    (*theory or local_theory*)
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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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      TheoryTarget.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 (TheoryTarget.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)
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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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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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  |> setmp Output.do_toplevel_errors false;
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fun program f =
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  Output.ML_errors (fn () => debugging f () handle exn => error (exn_message exn)) ();
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end;
wenzelm@20128
   327
wenzelm@5828
   328
wenzelm@16815
   329
(* node transactions and recovery from stale theories *)
wenzelm@6689
   330
wenzelm@16815
   331
(*NB: proof commands should be non-destructive!*)
wenzelm@7022
   332
wenzelm@6689
   333
local
wenzelm@6689
   334
wenzelm@16452
   335
fun is_stale state = Context.is_stale (theory_of state) handle UNDEF => false;
wenzelm@6689
   336
wenzelm@18685
   337
val stale_theory = ERROR "Stale theory encountered after succesful execution!";
wenzelm@16815
   338
wenzelm@21177
   339
fun map_theory f = History.map
wenzelm@21177
   340
  (fn Theory (gthy, _) => Theory (Context.mapping f (LocalTheory.raw_theory f) gthy, NONE)
wenzelm@21177
   341
    | node => node);
wenzelm@6689
   342
skalberg@15531
   343
fun return (result, NONE) = result
skalberg@15531
   344
  | return (result, SOME exn) = raise FAILURE (result, exn);
wenzelm@7022
   345
wenzelm@6689
   346
in
wenzelm@6689
   347
wenzelm@20128
   348
fun transaction hist f (node, term) =
wenzelm@20128
   349
  let
wenzelm@21177
   350
    val cont_node = map_theory Theory.checkpoint node;
wenzelm@21177
   351
    val back_node = map_theory Theory.copy cont_node;
wenzelm@20128
   352
    fun state nd = State (SOME (nd, term));
wenzelm@20128
   353
    fun normal_state nd = (state nd, NONE);
wenzelm@20128
   354
    fun error_state nd exn = (state nd, SOME exn);
wenzelm@6689
   355
wenzelm@20128
   356
    val (result, err) =
wenzelm@20128
   357
      cont_node
wenzelm@20128
   358
      |> (f
wenzelm@21177
   359
          |> (if hist then History.apply' (History.current back_node) else History.map)
wenzelm@20128
   360
          |> controlled_execution)
wenzelm@20128
   361
      |> normal_state
wenzelm@20128
   362
      handle exn => error_state cont_node exn;
wenzelm@20128
   363
  in
wenzelm@20128
   364
    if is_stale result
wenzelm@20128
   365
    then return (error_state back_node (the_default stale_theory err))
wenzelm@20128
   366
    else return (result, err)
wenzelm@20128
   367
  end;
wenzelm@6689
   368
wenzelm@6689
   369
end;
wenzelm@6689
   370
wenzelm@6689
   371
wenzelm@6689
   372
(* primitive transitions *)
wenzelm@6689
   373
wenzelm@18563
   374
(*Note: Recovery from stale theories is provided only for theory-level
wenzelm@18589
   375
  operations via Transaction.  Other node or state operations should
wenzelm@18589
   376
  not touch theories at all.  Interrupts are enabled only for Keep and
wenzelm@18589
   377
  Transaction.*)
wenzelm@5828
   378
wenzelm@5828
   379
datatype trans =
wenzelm@18563
   380
  Reset |                                               (*empty toplevel*)
wenzelm@8465
   381
  Init of (bool -> node) * ((node -> unit) * (node -> unit)) |
wenzelm@18563
   382
                                                        (*init node; with exit/kill operation*)
wenzelm@18563
   383
  Exit |                                                (*conclude node*)
wenzelm@18563
   384
  Kill |                                                (*abort node*)
wenzelm@20128
   385
  History of node History.T -> node History.T |         (*history operation (undo etc.)*)
wenzelm@18563
   386
  Keep of bool -> state -> unit |                       (*peek at state*)
wenzelm@18592
   387
  Transaction of bool * (bool -> node -> node);         (*node transaction*)
wenzelm@6689
   388
skalberg@15531
   389
fun undo_limit int = if int then NONE else SOME 0;
wenzelm@6689
   390
wenzelm@6689
   391
local
wenzelm@5828
   392
wenzelm@6689
   393
fun apply_tr _ Reset _ = toplevel
skalberg@15531
   394
  | apply_tr int (Init (f, term)) (State NONE) =
skalberg@15531
   395
      State (SOME (History.init (undo_limit int) (f int), term))
skalberg@15531
   396
  | apply_tr _ (Init _ ) (State (SOME _)) = raise UNDEF
skalberg@15531
   397
  | apply_tr _ Exit (State NONE) = raise UNDEF
skalberg@15531
   398
  | apply_tr _ Exit (State (SOME (node, (exit, _)))) =
skalberg@15531
   399
      (exit (History.current node); State NONE)
skalberg@15531
   400
  | apply_tr _ Kill (State NONE) = raise UNDEF
skalberg@15531
   401
  | apply_tr _ Kill (State (SOME (node, (_, kill)))) =
skalberg@15531
   402
      (kill (History.current node); State NONE)
skalberg@15531
   403
  | apply_tr _ (History _) (State NONE) = raise UNDEF
skalberg@15531
   404
  | apply_tr _ (History f) (State (SOME (node, term))) = State (SOME (f node, term))
wenzelm@20128
   405
  | apply_tr int (Keep f) state =
wenzelm@20128
   406
      controlled_execution (fn x => tap (f int) x) state
wenzelm@20128
   407
  | apply_tr _ (Transaction _) (State NONE) = raise UNDEF
wenzelm@20128
   408
  | apply_tr int (Transaction (hist, f)) (State (SOME state)) =
wenzelm@20128
   409
      transaction hist (fn x => f int x) state;
wenzelm@5828
   410
wenzelm@6689
   411
fun apply_union _ [] state = raise FAILURE (state, UNDEF)
wenzelm@6689
   412
  | apply_union int (tr :: trs) state =
wenzelm@18685
   413
      apply_tr int tr state
wenzelm@6689
   414
        handle UNDEF => apply_union int trs state
wenzelm@6689
   415
          | FAILURE (alt_state, UNDEF) => apply_union int trs alt_state
wenzelm@6689
   416
          | exn as FAILURE _ => raise exn
wenzelm@6689
   417
          | exn => raise FAILURE (state, exn);
wenzelm@6689
   418
wenzelm@6689
   419
in
wenzelm@6689
   420
skalberg@15531
   421
fun apply_trans int trs state = (apply_union int trs state, NONE)
skalberg@15531
   422
  handle FAILURE (alt_state, exn) => (alt_state, SOME exn) | exn => (state, SOME exn);
wenzelm@6689
   423
wenzelm@6689
   424
end;
wenzelm@5828
   425
wenzelm@5828
   426
wenzelm@5828
   427
(* datatype transition *)
wenzelm@5828
   428
wenzelm@5828
   429
datatype transition = Transition of
wenzelm@16815
   430
 {name: string,                        (*command name*)
wenzelm@16815
   431
  pos: Position.T,                     (*source position*)
wenzelm@16815
   432
  source: OuterLex.token list option,  (*source text*)
wenzelm@16815
   433
  int_only: bool,                      (*interactive-only*)
wenzelm@16815
   434
  print: string list,                  (*print modes (union)*)
wenzelm@16815
   435
  no_timing: bool,                     (*suppress timing*)
wenzelm@16815
   436
  trans: trans list};                  (*primitive transitions (union)*)
wenzelm@5828
   437
wenzelm@14923
   438
fun make_transition (name, pos, source, int_only, print, no_timing, trans) =
wenzelm@14923
   439
  Transition {name = name, pos = pos, source = source,
wenzelm@14923
   440
    int_only = int_only, print = print, no_timing = no_timing, trans = trans};
wenzelm@5828
   441
wenzelm@14923
   442
fun map_transition f (Transition {name, pos, source, int_only, print, no_timing, trans}) =
wenzelm@14923
   443
  make_transition (f (name, pos, source, int_only, print, no_timing, trans));
wenzelm@5828
   444
wenzelm@16607
   445
val empty = make_transition ("<unknown>", Position.none, NONE, false, [], false, []);
wenzelm@14923
   446
wenzelm@14923
   447
fun name_of (Transition {name, ...}) = name;
wenzelm@14923
   448
fun source_of (Transition {source, ...}) = source;
wenzelm@5828
   449
wenzelm@5828
   450
wenzelm@5828
   451
(* diagnostics *)
wenzelm@5828
   452
wenzelm@5828
   453
fun str_of_transition (Transition {name, pos, ...}) = quote name ^ Position.str_of pos;
wenzelm@5828
   454
wenzelm@5828
   455
fun command_msg msg tr = msg ^ "command " ^ str_of_transition tr;
wenzelm@5828
   456
fun at_command tr = command_msg "At " tr ^ ".";
wenzelm@5828
   457
wenzelm@5828
   458
fun type_error tr state =
wenzelm@18685
   459
  ERROR (command_msg "Illegal application of " tr ^ " " ^ str_of_state state);
wenzelm@5828
   460
wenzelm@5828
   461
wenzelm@5828
   462
(* modify transitions *)
wenzelm@5828
   463
wenzelm@14923
   464
fun name nm = map_transition (fn (_, pos, source, int_only, print, no_timing, trans) =>
wenzelm@14923
   465
  (nm, pos, source, int_only, print, no_timing, trans));
wenzelm@5828
   466
wenzelm@14923
   467
fun position pos = map_transition (fn (name, _, source, int_only, print, no_timing, trans) =>
wenzelm@14923
   468
  (name, pos, source, int_only, print, no_timing, trans));
wenzelm@9010
   469
wenzelm@14923
   470
fun source src = map_transition (fn (name, pos, _, int_only, print, no_timing, trans) =>
skalberg@15531
   471
  (name, pos, SOME src, int_only, print, no_timing, trans));
wenzelm@5828
   472
wenzelm@14923
   473
fun interactive int_only = map_transition (fn (name, pos, source, _, print, no_timing, trans) =>
wenzelm@14923
   474
  (name, pos, source, int_only, print, no_timing, trans));
wenzelm@14923
   475
wenzelm@17363
   476
val no_timing = map_transition (fn (name, pos, source, int_only, print, _, trans) =>
wenzelm@17363
   477
  (name, pos, source, int_only, print, true, trans));
wenzelm@17363
   478
wenzelm@17363
   479
fun add_trans tr = map_transition (fn (name, pos, source, int_only, print, no_timing, trans) =>
wenzelm@17363
   480
  (name, pos, source, int_only, print, no_timing, trans @ [tr]));
wenzelm@17363
   481
wenzelm@16607
   482
fun print' mode = map_transition (fn (name, pos, source, int_only, print, no_timing, trans) =>
wenzelm@16607
   483
  (name, pos, source, int_only, insert (op =) mode print, no_timing, trans));
wenzelm@16607
   484
wenzelm@16607
   485
val print = print' "";
wenzelm@5828
   486
wenzelm@17363
   487
val three_buffersN = "three_buffers";
wenzelm@17363
   488
val print3 = print' three_buffersN;
wenzelm@5828
   489
wenzelm@5828
   490
wenzelm@21007
   491
(* basic transitions *)
wenzelm@5828
   492
wenzelm@5828
   493
val reset = add_trans Reset;
wenzelm@6689
   494
fun init f exit kill = add_trans (Init (f, (exit, kill)));
wenzelm@6689
   495
val exit = add_trans Exit;
wenzelm@6689
   496
val kill = add_trans Kill;
wenzelm@20128
   497
val history = add_trans o History;
wenzelm@7612
   498
val keep' = add_trans o Keep;
wenzelm@18592
   499
fun map_current f = add_trans (Transaction (false, f));
wenzelm@18592
   500
fun app_current f = add_trans (Transaction (true, f));
wenzelm@5828
   501
wenzelm@7612
   502
fun keep f = add_trans (Keep (fn _ => f));
wenzelm@5828
   503
fun imperative f = keep (fn _ => f ());
wenzelm@5828
   504
wenzelm@6689
   505
fun init_theory f exit kill =
wenzelm@20963
   506
  init (fn int => Theory (Context.Theory (f int), NONE))
wenzelm@20963
   507
    (fn Theory (Context.Theory thy, _) => exit thy | _ => raise UNDEF)
wenzelm@20963
   508
    (fn Theory (Context.Theory thy, _) => kill thy | _ => raise UNDEF);
wenzelm@5828
   509
wenzelm@21007
   510
val unknown_theory = imperative (fn () => warning "Unknown theory context");
wenzelm@21007
   511
val unknown_proof = imperative (fn () => warning "Unknown proof context");
wenzelm@21007
   512
val unknown_context = imperative (fn () => warning "Unknown context");
wenzelm@15668
   513
wenzelm@21007
   514
wenzelm@21007
   515
(* theory transitions *)
wenzelm@15668
   516
wenzelm@20963
   517
fun theory' f = app_current (fn int =>
wenzelm@20963
   518
  (fn Theory (Context.Theory thy, _) => Theory (Context.Theory (f int thy), NONE)
wenzelm@20963
   519
    | _ => raise UNDEF));
wenzelm@20963
   520
wenzelm@20963
   521
fun theory f = theory' (K f);
wenzelm@20963
   522
wenzelm@20985
   523
fun begin_local_theory begin f = app_current (fn int =>
wenzelm@20963
   524
  (fn Theory (Context.Theory thy, _) =>
wenzelm@20963
   525
        let
wenzelm@20985
   526
          val lthy = f thy;
wenzelm@20963
   527
          val (ctxt, gthy) =
wenzelm@20963
   528
            if begin then (lthy, Context.Proof lthy)
wenzelm@20985
   529
            else lthy |> LocalTheory.exit int ||> Context.Theory;
wenzelm@20963
   530
        in Theory (gthy, SOME ctxt) end
wenzelm@20963
   531
    | _ => raise UNDEF));
wenzelm@17076
   532
wenzelm@21007
   533
val end_local_theory = app_current (fn int =>
wenzelm@21007
   534
  (fn Theory (Context.Proof lthy, _) =>
wenzelm@21007
   535
      let val (ctxt', thy') = LocalTheory.exit int lthy
wenzelm@21007
   536
      in Theory (Context.Theory thy', SOME ctxt') end
wenzelm@21007
   537
    | _ => raise UNDEF));
wenzelm@21007
   538
wenzelm@21007
   539
local
wenzelm@21007
   540
wenzelm@20963
   541
fun local_theory_presentation loc f g = app_current (fn int =>
wenzelm@20963
   542
  (fn Theory (Context.Theory thy, _) =>
wenzelm@20963
   543
        let val (ctxt', thy') = TheoryTarget.mapping loc f thy
wenzelm@20963
   544
        in Theory (Context.Theory thy', SOME ctxt') end
wenzelm@20963
   545
    | Theory (Context.Proof lthy, _) =>
wenzelm@20963
   546
        let val (ctxt', lthy') =
wenzelm@21277
   547
          if is_none loc then f lthy |> (fn lthy' => (lthy', LocalTheory.restore lthy'))
wenzelm@20963
   548
          else lthy |> LocalTheory.raw_theory_result (TheoryTarget.mapping loc f)
wenzelm@20963
   549
        in Theory (Context.Proof lthy', SOME ctxt') end
wenzelm@20963
   550
    | _ => raise UNDEF) #> tap (g int));
wenzelm@15668
   551
wenzelm@21007
   552
in
wenzelm@21007
   553
wenzelm@20963
   554
fun local_theory loc f = local_theory_presentation loc f (K I);
wenzelm@20963
   555
fun present_local_theory loc g = local_theory_presentation loc I g;
wenzelm@18955
   556
wenzelm@21007
   557
end;
wenzelm@21007
   558
wenzelm@21007
   559
wenzelm@21007
   560
(* proof transitions *)
wenzelm@21007
   561
wenzelm@21007
   562
local
wenzelm@21007
   563
wenzelm@21007
   564
fun begin_proof init finish = app_current (fn int =>
wenzelm@21007
   565
  (fn Theory (gthy, _) =>
wenzelm@21007
   566
    let 
wenzelm@21007
   567
      val prf = init gthy;
wenzelm@19996
   568
      val schematic = Proof.schematic_goal prf;
wenzelm@19996
   569
    in
wenzelm@19996
   570
      if ! skip_proofs andalso schematic then
wenzelm@19996
   571
        warning "Cannot skip proof of schematic goal statement"
wenzelm@19996
   572
      else ();
wenzelm@19996
   573
      if ! skip_proofs andalso not schematic then
wenzelm@21007
   574
        SkipProof
wenzelm@21007
   575
          (History.init (undo_limit int) 0, (finish gthy (Proof.global_skip_proof int prf), gthy))
wenzelm@21007
   576
      else Proof (ProofHistory.init (undo_limit int) prf, (finish gthy, gthy))
wenzelm@19996
   577
    end
wenzelm@18592
   578
  | _ => raise UNDEF));
wenzelm@18563
   579
wenzelm@21007
   580
val global_finish = Context.Theory o ProofContext.theory_of;
wenzelm@21277
   581
val local_finish = Context.Proof o LocalTheory.restore;
wenzelm@21007
   582
wenzelm@21007
   583
fun mixed_finish (Context.Theory _) ctxt = global_finish ctxt
wenzelm@21007
   584
  | mixed_finish (Context.Proof lthy) ctxt =
wenzelm@21007
   585
      Context.Proof (LocalTheory.raw_theory (K (ProofContext.theory_of ctxt)) lthy);
wenzelm@21007
   586
wenzelm@21007
   587
in
wenzelm@21007
   588
wenzelm@21007
   589
fun local_theory_to_proof NONE f = begin_proof
wenzelm@21007
   590
      (fn Context.Theory thy => f (TheoryTarget.init NONE thy)
wenzelm@21007
   591
        | Context.Proof lthy => f lthy)
wenzelm@21007
   592
      (fn Context.Theory _ => global_finish
wenzelm@21007
   593
        | Context.Proof _ => local_finish)
wenzelm@21007
   594
  | local_theory_to_proof loc f =
wenzelm@21007
   595
      begin_proof (f o TheoryTarget.init loc o Context.theory_of) mixed_finish;
wenzelm@21007
   596
wenzelm@21007
   597
fun theory_to_proof f =
wenzelm@21007
   598
  begin_proof (fn Context.Theory thy => f thy | _ => raise UNDEF) (K global_finish);
wenzelm@21007
   599
wenzelm@21007
   600
end;
wenzelm@21007
   601
wenzelm@21007
   602
fun end_proof f = map_current (fn int =>
wenzelm@21007
   603
  (fn Proof (prf, (finish, orig_gthy)) =>
wenzelm@21007
   604
        let val state = ProofHistory.current prf in
wenzelm@21007
   605
          if can (Proof.assert_bottom true) state then
wenzelm@21007
   606
            let
wenzelm@21007
   607
              val ctxt' = f int state;
wenzelm@21007
   608
              val gthy' = finish ctxt';
wenzelm@21007
   609
            in Theory (gthy', SOME ctxt') end
wenzelm@21007
   610
          else raise UNDEF
wenzelm@21007
   611
        end
wenzelm@21007
   612
    | SkipProof (h, (gthy, _)) =>
wenzelm@21007
   613
        if History.current h = 0 then Theory (gthy, NONE) else raise UNDEF
wenzelm@21007
   614
    | _ => raise UNDEF));
wenzelm@21007
   615
wenzelm@21007
   616
val forget_proof = map_current (fn _ =>
wenzelm@21007
   617
  (fn Proof (_, (_, orig_gthy)) => Theory (orig_gthy, NONE)
wenzelm@21007
   618
    | SkipProof (_, (_, orig_gthy)) => Theory (orig_gthy, NONE)
wenzelm@21007
   619
    | _ => raise UNDEF));
wenzelm@21007
   620
wenzelm@21177
   621
fun present_proof f = map_current (fn int =>
wenzelm@21177
   622
  (fn Proof (prf, x) => Proof (ProofHistory.apply I prf, x)
wenzelm@21177
   623
    | SkipProof (h, x) => SkipProof (History.apply I h, x)
wenzelm@21177
   624
    | _ => raise UNDEF) #> tap (f int));
wenzelm@21177
   625
wenzelm@17904
   626
fun proofs' f = map_current (fn int =>
wenzelm@21007
   627
  (fn Proof (prf, x) => Proof (ProofHistory.applys (f int) prf, x)
wenzelm@21007
   628
    | SkipProof (h, x) => SkipProof (History.apply I h, x)
wenzelm@16815
   629
    | _ => raise UNDEF));
wenzelm@15668
   630
wenzelm@17904
   631
fun proof' f = proofs' (Seq.single oo f);
wenzelm@17904
   632
val proofs = proofs' o K;
wenzelm@6689
   633
val proof = proof' o K;
wenzelm@16815
   634
wenzelm@16815
   635
fun actual_proof f = map_current (fn _ =>
wenzelm@21007
   636
  (fn Proof (prf, x) => Proof (f prf, x)
wenzelm@20963
   637
    | _ => raise UNDEF));
wenzelm@16815
   638
wenzelm@16815
   639
fun skip_proof f = map_current (fn _ =>
wenzelm@21007
   640
  (fn SkipProof (h, x) => SkipProof (f h, x)
wenzelm@18563
   641
    | _ => raise UNDEF));
wenzelm@18563
   642
wenzelm@16815
   643
fun skip_proof_to_theory p = map_current (fn _ =>
wenzelm@21007
   644
  (fn SkipProof (h, (gthy, _)) =>
wenzelm@21007
   645
    if p (History.current h) then Theory (gthy, NONE)
wenzelm@17904
   646
    else raise UNDEF
wenzelm@17904
   647
  | _ => raise UNDEF));
wenzelm@5828
   648
wenzelm@5828
   649
wenzelm@5828
   650
wenzelm@5828
   651
(** toplevel transactions **)
wenzelm@5828
   652
wenzelm@5828
   653
(* apply transitions *)
wenzelm@5828
   654
wenzelm@6664
   655
local
wenzelm@6664
   656
wenzelm@9010
   657
fun app int (tr as Transition {trans, int_only, print, no_timing, ...}) state =
wenzelm@5828
   658
  let
wenzelm@16682
   659
    val _ = conditional (not int andalso int_only) (fn () =>
wenzelm@16682
   660
      warning (command_msg "Interactive-only " tr));
wenzelm@16682
   661
wenzelm@18685
   662
    fun do_timing f x = (Output.info (command_msg "" tr); timeap f x);
wenzelm@16682
   663
    fun do_profiling f x = profile (! profiling) f x;
wenzelm@16682
   664
wenzelm@6689
   665
    val (result, opt_exn) =
wenzelm@16729
   666
       state |> (apply_trans int trans
wenzelm@16729
   667
        |> (if ! profiling > 0 then do_profiling else I)
wenzelm@16729
   668
        |> (if ! profiling > 0 orelse ! timing andalso not no_timing then do_timing else I));
wenzelm@16607
   669
    val _ = conditional (int andalso not (! quiet) andalso
wenzelm@20664
   670
        exists (member (op =) print) ("" :: ! print_mode))
wenzelm@16607
   671
      (fn () => print_state false result);
skalberg@15570
   672
  in (result, Option.map (fn UNDEF => type_error tr state | exn => exn) opt_exn) end;
wenzelm@6664
   673
wenzelm@6664
   674
in
wenzelm@5828
   675
wenzelm@6689
   676
fun apply int tr st =
wenzelm@6965
   677
  (case app int tr st of
skalberg@15531
   678
    (_, SOME TERMINATE) => NONE
skalberg@15531
   679
  | (_, SOME RESTART) => SOME (toplevel, NONE)
skalberg@15531
   680
  | (state', SOME (EXCURSION_FAIL exn_info)) => SOME (state', SOME exn_info)
skalberg@15531
   681
  | (state', SOME exn) => SOME (state', SOME (exn, at_command tr))
skalberg@15531
   682
  | (state', NONE) => SOME (state', NONE));
wenzelm@6664
   683
wenzelm@6664
   684
end;
wenzelm@5828
   685
wenzelm@5828
   686
wenzelm@17076
   687
(* excursion: toplevel -- apply transformers/presentation -- toplevel *)
wenzelm@5828
   688
wenzelm@6664
   689
local
wenzelm@6664
   690
wenzelm@5828
   691
fun excur [] x = x
wenzelm@17076
   692
  | excur ((tr, pr) :: trs) (st, res) =
wenzelm@17321
   693
      (case apply (! interact) tr st of
skalberg@15531
   694
        SOME (st', NONE) =>
wenzelm@18685
   695
          excur trs (st', pr st st' res handle exn =>
wenzelm@10324
   696
            raise EXCURSION_FAIL (exn, "Presentation failed\n" ^ at_command tr))
skalberg@15531
   697
      | SOME (st', SOME exn_info) => raise EXCURSION_FAIL exn_info
skalberg@15531
   698
      | NONE => raise EXCURSION_FAIL (TERMINATE, at_command tr));
wenzelm@5828
   699
wenzelm@17076
   700
fun no_pr _ _ _ = ();
wenzelm@17076
   701
wenzelm@6664
   702
in
wenzelm@6664
   703
wenzelm@17076
   704
fun present_excursion trs res =
skalberg@15531
   705
  (case excur trs (State NONE, res) of
skalberg@15531
   706
    (State NONE, res') => res'
wenzelm@18685
   707
  | _ => error "Unfinished development at end of input")
wenzelm@9134
   708
  handle exn => error (exn_message exn);
wenzelm@9134
   709
wenzelm@17076
   710
fun excursion trs = present_excursion (map (rpair no_pr) trs) ();
wenzelm@7062
   711
wenzelm@6664
   712
end;
wenzelm@6664
   713
wenzelm@5828
   714
wenzelm@5828
   715
wenzelm@5828
   716
(** interactive transformations **)
wenzelm@5828
   717
wenzelm@5828
   718
(* the global state reference *)
wenzelm@5828
   719
skalberg@15531
   720
val global_state = ref (toplevel, NONE: (exn * string) option);
wenzelm@5828
   721
skalberg@15531
   722
fun set_state state = global_state := (state, NONE);
wenzelm@5828
   723
fun get_state () = fst (! global_state);
wenzelm@5828
   724
fun exn () = snd (! global_state);
wenzelm@5828
   725
wenzelm@5828
   726
wenzelm@6965
   727
(* the Isar source of transitions *)
wenzelm@6965
   728
nipkow@14091
   729
type 'a isar =
wenzelm@6965
   730
  (transition, (transition option,
wenzelm@12881
   731
    (OuterLex.token, (OuterLex.token option, (OuterLex.token, (OuterLex.token,
nipkow@14091
   732
      Position.T * (Symbol.symbol, (string, 'a) Source.source) Source.source)
wenzelm@12881
   733
          Source.source) Source.source) Source.source) Source.source) Source.source) Source.source;
wenzelm@6965
   734
wenzelm@6965
   735
wenzelm@5828
   736
(* apply transformers to global state *)
wenzelm@5828
   737
wenzelm@14985
   738
nonfix >> >>>;
wenzelm@5828
   739
wenzelm@5828
   740
fun >> tr =
wenzelm@5828
   741
  (case apply true tr (get_state ()) of
skalberg@15531
   742
    NONE => false
skalberg@15531
   743
  | SOME (state', exn_info) =>
wenzelm@5828
   744
      (global_state := (state', exn_info);
wenzelm@16729
   745
        print_exn exn_info;
wenzelm@5828
   746
        true));
wenzelm@5828
   747
wenzelm@14985
   748
fun >>> [] = ()
wenzelm@14985
   749
  | >>> (tr :: trs) = if >> tr then >>> trs else ();
wenzelm@14985
   750
wenzelm@17513
   751
(*Spurious interrupts ahead!  Race condition?*)
wenzelm@17513
   752
fun get_interrupt src = SOME (Source.get_single src) handle Interrupt => NONE;
wenzelm@7602
   753
wenzelm@20928
   754
fun warn_secure () =
wenzelm@20928
   755
  let val secure = Secure.is_secure ()
wenzelm@20928
   756
  in if secure then warning "Cannot exit to ML in secure mode" else (); secure end;
wenzelm@20928
   757
wenzelm@5828
   758
fun raw_loop src =
wenzelm@7602
   759
  (case get_interrupt (Source.set_prompt (prompt_state (get_state ())) src) of
skalberg@15531
   760
    NONE => (writeln "\nInterrupt."; raw_loop src)
wenzelm@20928
   761
  | SOME NONE => if warn_secure () then quit () else ()
wenzelm@20928
   762
  | SOME (SOME (tr, src')) =>
wenzelm@20928
   763
      if >> tr orelse warn_secure () then raw_loop src'
wenzelm@20928
   764
      else ());
wenzelm@5828
   765
wenzelm@12987
   766
fun loop src = ignore_interrupt raw_loop src;
wenzelm@5828
   767
wenzelm@5828
   768
end;