(* Title: Pure/Isar/toplevel.ML
ID: $Id$
Author: Markus Wenzel, TU Muenchen
The Isabelle/Isar toplevel.
*)
signature TOPLEVEL =
sig
datatype node = Theory of theory | Proof of ProofHistory.T
type state
val toplevel: state
val prompt_state_default: state -> string
val prompt_state_fn: (state -> string) ref
val print_state_default: state -> unit
val print_state_fn: (state -> unit) ref
val print_state: state -> unit
exception UNDEF
val node_history_of: state -> node History.T
val node_of: state -> node
val node_case: (theory -> 'a) -> (Proof.state -> 'a) -> state -> 'a
val theory_of: state -> theory
val sign_of: state -> Sign.sg
val proof_of: state -> Proof.state
type transition
exception TERMINATE
exception RESTART
exception BREAK of state
val undo_limit: bool -> int option
val empty: transition
val name: string -> transition -> transition
val position: Position.T -> transition -> transition
val interactive: bool -> transition -> transition
val print: transition -> transition
val reset: transition -> transition
val init: (state -> node) -> (node -> unit) -> (node -> unit) -> transition -> transition
val exit: transition -> transition
val kill: transition -> transition
val keep: (state -> unit) -> transition -> transition
val history: (node History.T -> node History.T) -> transition -> transition
val imperative: (unit -> unit) -> transition -> transition
val init_theory: (unit -> theory) -> (theory -> unit) -> (theory -> unit)
-> transition -> transition
val theory: (theory -> theory) -> transition -> transition
val theory_to_proof: (bool -> theory -> ProofHistory.T) -> transition -> transition
val proof: (ProofHistory.T -> ProofHistory.T) -> transition -> transition
val proof': (bool -> ProofHistory.T -> ProofHistory.T) -> transition -> transition
val proof_to_theory: (ProofHistory.T -> theory) -> transition -> transition
val trace: bool ref
val exn_message: exn -> string
type isar
val apply: bool -> transition -> state -> (state * (exn * string) option) option
val excursion: transition list -> unit
val set_state: state -> unit
val get_state: unit -> state
val exn: unit -> (exn * string) option
val >> : transition -> bool
val loop: isar -> unit
end;
structure Toplevel(*: TOPLEVEL *)=
struct
(** toplevel state **)
(* datatype node *)
datatype node =
Theory of theory |
Proof of ProofHistory.T;
fun str_of_node (Theory _) = "in theory mode"
| str_of_node (Proof _) = "in proof mode";
fun print_node (Theory thy) = Pretty.writeln (Pretty.block
[Pretty.str "Theory:", Pretty.brk 1, Pretty.str (PureThy.get_name thy),
Pretty.str " =", Pretty.brk 1, Display.pretty_theory thy])
| print_node (Proof prf) =
(writeln ("Proof: step #" ^ string_of_int (ProofHistory.position prf));
Proof.print_state (ProofHistory.current prf));
(* datatype state *)
datatype state = State of (node History.T * ((node -> unit) * (node -> unit))) list;
val toplevel = State [];
fun append_states (State ns) (State ms) = State (ns @ ms);
fun str_of_state (State []) = "at top level"
| str_of_state (State ((node, _) :: _)) = str_of_node (History.current node);
(* prompt_state hook *)
fun prompt_state_default (State nodes) =
let val len = length nodes
in (if len < 2 then "" else string_of_int len) ^ Source.default_prompt end;
val prompt_state_fn = ref prompt_state_default;
fun prompt_state state = ! prompt_state_fn state;
(* print_state hook *)
fun print_topnode (State []) = ()
| print_topnode (State ((node, _) :: _)) = print_node (History.current node);
fun print_state_default state =
let val ref (begin_state, end_state, _) = Goals.current_goals_markers in
if begin_state = "" then () else writeln begin_state;
print_topnode state;
if end_state = "" then () else writeln end_state
end;
val print_state_fn = ref print_state_default;
fun print_state state = ! print_state_fn state;
(* top node *)
exception UNDEF;
fun node_history_of (State []) = raise UNDEF
| node_history_of (State ((node, _) :: _)) = node;
val node_of = History.current o node_history_of;
fun node_case f g state =
(case node_of state of
Theory thy => f thy
| Proof prf => g (ProofHistory.current prf));
val theory_of = node_case I Proof.theory_of;
val sign_of = Theory.sign_of o theory_of;
val proof_of = node_case (fn _ => raise UNDEF) I;
(** toplevel transitions **)
exception TERMINATE;
exception RESTART;
exception BREAK of state;
exception FAIL of exn * string;
exception ROLLBACK of state * exn option;
exception FAILURE of state * exn;
(* recovery from stale signatures *)
local
fun is_stale state = Sign.is_stale (sign_of state) handle UNDEF => false;
fun checkpoint_node true (Theory thy) = Theory (PureThy.checkpoint thy)
| checkpoint_node _ node = node;
fun copy_node true (Theory thy) = Theory (Theory.copy thy)
| copy_node _ node = node;
in
fun node_trans _ _ _ (State []) = raise UNDEF
| node_trans int hist f (State ((node, term) :: nodes)) =
let
fun mk_state nd = State ((nd, term) :: nodes);
val cont_node = History.map (checkpoint_node int) node;
val back_node = History.map (copy_node int) cont_node;
val trans = if hist then History.apply_copy (copy_node int) else History.map;
val (result, opt_exn) = (mk_state (transform_error (trans (f int)) cont_node), None)
handle exn => (mk_state cont_node, Some exn);
in
if is_stale result then raise ROLLBACK (mk_state back_node, opt_exn)
else (case opt_exn of None => result | Some exn => raise FAILURE (result, exn))
end;
fun check_stale state =
if not (is_stale state) then ()
else warning "Stale signature encountered! Should redo current theory from start.";
end;
(* primitive transitions *)
(*Important note: recovery from stale signatures is provided only for
theory-level operations via MapCurrent and AppCurrent. Other node
or state operations should not touch signatures at all.*)
datatype trans =
Reset | (*empty toplevel*)
Init of (state -> node) * ((node -> unit) * (node -> unit)) |
(*push node; provide exit/kill operation*)
Exit | (*pop node*)
Kill | (*abort node*)
Keep of state -> unit | (*peek at state*)
History of node History.T -> node History.T | (*history operation (undo etc.)*)
MapCurrent of bool -> node -> node | (*change node, bypassing history*)
AppCurrent of bool -> node -> node; (*change node, recording history*)
fun undo_limit int = if int then None else Some 0;
local
fun apply_tr _ Reset _ = toplevel
| apply_tr int (Init (f, term)) (state as State nodes) =
State ((History.init (undo_limit int) (f state), term) :: nodes)
| apply_tr _ Exit (State []) = raise UNDEF
| apply_tr _ Exit (State ((node, (exit, _)):: nodes)) =
(exit (History.current node); State nodes)
| apply_tr _ Kill (State []) = raise UNDEF
| apply_tr _ Kill (State ((node, (_, kill)) :: nodes)) =
(kill (History.current node); State nodes)
| apply_tr _ (Keep f) state = (f state; state)
| apply_tr _ (History _) (State []) = raise UNDEF
| apply_tr _ (History f) (State ((node, term) :: nodes)) = State ((f node, term) :: nodes)
| apply_tr int (MapCurrent f) state = node_trans int false f state
| apply_tr int (AppCurrent f) state = node_trans int true f state;
fun apply_union _ [] state = raise FAILURE (state, UNDEF)
| apply_union int (tr :: trs) state =
transform_error (apply_tr int tr) state
handle UNDEF => apply_union int trs state
| FAILURE (alt_state, UNDEF) => apply_union int trs alt_state
| exn as FAILURE _ => raise exn
| exn => raise FAILURE (state, exn);
in
fun apply_trans int trs state = (apply_union int trs state, None)
handle FAILURE (alt_state, exn) => (alt_state, Some exn) | exn => (state, Some exn);
end;
(* datatype transition *)
datatype transition = Transition of
{name: string,
pos: Position.T,
int_only: bool,
print: bool,
trans: trans list};
fun make_transition (name, pos, int_only, print, trans) =
Transition {name = name, pos = pos, int_only = int_only, print = print, trans = trans};
fun map_transition f (Transition {name, pos, int_only, print, trans}) =
make_transition (f (name, pos, int_only, print, trans));
val empty = make_transition ("<unknown>", Position.none, false, false, []);
(* diagnostics *)
fun str_of_transition (Transition {name, pos, ...}) = quote name ^ Position.str_of pos;
fun command_msg msg tr = msg ^ "command " ^ str_of_transition tr;
fun at_command tr = command_msg "At " tr ^ ".";
fun type_error tr state =
ERROR_MESSAGE (command_msg "Illegal application of " tr ^ " " ^ str_of_state state);
(* modify transitions *)
fun name nm = map_transition
(fn (_, pos, int_only, print, trans) => (nm, pos, int_only, print, trans));
fun position pos = map_transition
(fn (name, _, int_only, print, trans) => (name, pos, int_only, print, trans));
fun interactive int_only = map_transition
(fn (name, pos, _, print, trans) => (name, pos, int_only, print, trans));
val print = map_transition
(fn (name, pos, int_only, _, trans) => (name, pos, int_only, true, trans));
fun add_trans tr = map_transition
(fn (name, pos, int_only, print, trans) => (name, pos, int_only, print, trans @ [tr]));
(* build transitions *)
val reset = add_trans Reset;
fun init f exit kill = add_trans (Init (f, (exit, kill)));
val exit = add_trans Exit;
val kill = add_trans Kill;
val keep = add_trans o Keep;
val history = add_trans o History;
val map_current = add_trans o MapCurrent;
val app_current = add_trans o AppCurrent;
fun imperative f = keep (fn _ => f ());
fun init_theory f exit kill =
init (fn _ => Theory (f ()))
(fn Theory thy => exit thy | _ => raise UNDEF)
(fn Theory thy => kill thy | _ => raise UNDEF);
fun theory f = app_current (fn _ => (fn Theory thy => Theory (f thy) | _ => raise UNDEF));
fun theory_to_proof f =
app_current (fn int => (fn Theory thy => Proof (f int thy) | _ => raise UNDEF));
fun proof' f = map_current (fn int => (fn Proof prf => Proof (f int prf) | _ => raise UNDEF));
val proof = proof' o K;
fun proof_to_theory f = map_current (fn _ => (fn Proof prf => Theory (f prf) | _ => raise UNDEF));
(** toplevel transactions **)
val trace = ref false;
(* print exceptions *)
fun raised name = "exception " ^ name ^ " raised";
fun raised_msg name msg = raised name ^ ": " ^ msg;
fun exn_message TERMINATE = "Exit."
| exn_message RESTART = "Restart."
| exn_message (BREAK _) = "Break."
| exn_message (FAIL (exn, msg)) = cat_lines [exn_message exn, msg]
| exn_message Interrupt = "Interrupt (exec)."
| exn_message ERROR = "ERROR."
| exn_message (ERROR_MESSAGE msg) = msg
| exn_message (THEORY (msg, _)) = msg
| exn_message (ProofContext.CONTEXT (msg, _)) = msg
| exn_message (Proof.STATE (msg, _)) = msg
| exn_message (ProofHistory.FAIL msg) = msg
| exn_message (Attrib.ATTRIB_FAIL info) = fail_message "attribute" info
| exn_message (Method.METHOD_FAIL info) = fail_message "method" info
| exn_message (Syntax.AST (msg, _)) = raised_msg "AST" msg
| exn_message (TYPE (msg, _, _)) = raised_msg "TYPE" msg
| exn_message (TERM (msg, _)) = raised_msg "TERM" msg
| exn_message (THM (msg, _, _)) = raised_msg "THM" msg
| exn_message Library.OPTION = raised "Library.OPTION"
| exn_message (Library.LIST msg) = raised_msg "Library.LIST" msg
| exn_message exn = General.exnMessage exn
and fail_message kind ((name, pos), exn) =
"Error in " ^ kind ^ " " ^ name ^ Position.str_of pos ^ ":\n" ^ exn_message exn;
fun print_exn None = ()
| print_exn (Some (exn, s)) = error_msg (cat_lines [exn_message exn, s]);
(* the Isar source of transitions *)
type isar =
(transition, (transition option,
(OuterLex.token, (OuterLex.token,
Position.T * (Symbol.symbol, (string, unit) Source.source) Source.source)
Source.source) Source.source) Source.source) Source.source;
(* transform interrupt (non-polymorphic) *)
fun transform_interrupt_state f x =
let val y = ref (None: (state * exn option) option);
in exhibit_interrupt (fn () => y := Some (f x)) (); the (! y) end;
fun transform_interrupt_isar f x =
let val y = ref (None: (transition * isar) option option);
in exhibit_interrupt (fn () => y := Some (f x)) (); the (! y) end;
(* apply transitions *)
local
fun app int (tr as Transition {trans, int_only, print, ...}) state =
let
val _ =
if int orelse not int_only then ()
else warning (command_msg "Executing interactive-only " tr);
val (result, opt_exn) =
(if ! trace then (writeln (command_msg "" tr); timeap) else I) (apply_trans int trans) state;
val _ = if int andalso print then print_state result else ();
in (result, apsome (fn UNDEF => type_error tr state | exn => exn) opt_exn) end;
in
fun apply int tr st =
(case transform_interrupt_state (app int tr) st of
(_, Some TERMINATE) => None
| (_, Some RESTART) => Some (toplevel, None)
| (state', Some (FAIL (exn_info as (BREAK break_state, _)))) =>
Some (append_states break_state state', Some exn_info)
| (state', Some (FAIL exn_info)) => Some (state', Some exn_info)
| (_, Some (ROLLBACK (back_state, opt_exn))) =>
(warning (command_msg "Rollback after " tr);
Some (back_state, apsome (fn exn => (exn, at_command tr)) opt_exn))
| (state', Some exn) => Some (state', Some (exn, at_command tr))
| (state', None) => Some (state', None));
end;
(* excursion: toplevel -- apply transformers -- toplevel *)
local
fun excur [] x = x
| excur (tr :: trs) x =
(case apply false tr x of
Some (x', None) => excur trs x'
| Some (x', Some exn_info) => raise FAIL exn_info
| None => raise FAIL (TERMINATE, at_command tr));
in
fun excursion trs =
(case excur trs (State []) of
State [] => ()
| _ => raise ERROR_MESSAGE "Open block(s) pending at end of input");
end;
(** interactive transformations **)
(* the global state reference *)
val global_state = ref (toplevel, None: (exn * string) option);
fun set_state state = global_state := (state, None);
fun get_state () = fst (! global_state);
fun exn () = snd (! global_state);
(* apply transformers to global state *)
nonfix >>;
fun >> tr =
(case apply true tr (get_state ()) of
None => false
| Some (state', exn_info) =>
(global_state := (state', exn_info);
check_stale state'; print_exn exn_info;
true));
fun get_interruptible src =
Some (transform_interrupt_isar Source.get_single src)
handle Interrupt => None;
fun raw_loop src =
(case get_interruptible (Source.set_prompt (prompt_state (get_state ())) src) of
None => (writeln "\nInterrupt (read)."; raw_loop src)
| Some None => ()
| Some (Some (tr, src')) => if >> tr then raw_loop src' else ());
fun loop src = mask_interrupt raw_loop src;
end;