src/Pure/Isar/proof.ML
author wenzelm
Thu Aug 30 19:18:49 2012 +0200 (2012-08-30)
changeset 49011 9c68e43502ce
parent 47815 43f677b3ae91
child 49012 8686c36fa27d
permissions -rw-r--r--
some support for registering forked proofs within Proof.state, using its bottom context;
tuned signature;
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(*  Title:      Pure/Isar/proof.ML
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    Author:     Markus Wenzel, TU Muenchen
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The Isar/VM proof language interpreter: maintains a structured flow of
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context elements, goals, refinements, and facts.
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*)
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signature PROOF =
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sig
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  type context = Proof.context
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  type method = Method.method
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  type state
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  val init: context -> state
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  val level: state -> int
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  val assert_bottom: bool -> state -> state
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  val context_of: state -> context
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  val theory_of: state -> theory
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  val map_context: (context -> context) -> state -> state
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  val map_context_result : (context -> 'a * context) -> state -> 'a * state
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  val map_contexts: (context -> context) -> state -> state
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  val propagate_ml_env: state -> state
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  val bind_terms: (indexname * term option) list -> state -> state
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  val put_thms: bool -> string * thm list option -> state -> state
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  val the_facts: state -> thm list
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  val the_fact: state -> thm
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  val set_facts: thm list -> state -> state
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  val reset_facts: state -> state
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  val assert_forward: state -> state
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  val assert_chain: state -> state
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  val assert_forward_or_chain: state -> state
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  val assert_backward: state -> state
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  val assert_no_chain: state -> state
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  val enter_forward: state -> state
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  val goal_message: (unit -> Pretty.T) -> state -> state
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  val pretty_state: int -> state -> Pretty.T list
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  val pretty_goals: bool -> state -> Pretty.T list
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  val refine: Method.text -> state -> state Seq.seq
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  val refine_end: Method.text -> state -> state Seq.seq
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  val refine_insert: thm list -> state -> state
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  val refine_goals: (context -> thm -> unit) -> context -> thm list -> state -> state Seq.seq
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  val raw_goal: state -> {context: context, facts: thm list, goal: thm}
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  val goal: state -> {context: context, facts: thm list, goal: thm}
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  val simple_goal: state -> {context: context, goal: thm}
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  val status_markup: state -> Markup.T
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  val let_bind: (term list * term) list -> state -> state
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  val let_bind_cmd: (string list * string) list -> state -> state
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  val write: Syntax.mode -> (term * mixfix) list -> state -> state
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  val write_cmd: Syntax.mode -> (string * mixfix) list -> state -> state
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  val fix: (binding * typ option * mixfix) list -> state -> state
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  val fix_cmd: (binding * string option * mixfix) list -> state -> state
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  val assm: Assumption.export ->
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    (Thm.binding * (term * term list) list) list -> state -> state
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  val assm_cmd: Assumption.export ->
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    (Attrib.binding * (string * string list) list) list -> state -> state
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  val assume: (Thm.binding * (term * term list) list) list -> state -> state
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  val assume_cmd: (Attrib.binding * (string * string list) list) list -> state -> state
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  val presume: (Thm.binding * (term * term list) list) list -> state -> state
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  val presume_cmd: (Attrib.binding * (string * string list) list) list -> state -> state
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  val def: (Thm.binding * ((binding * mixfix) * (term * term list))) list -> state -> state
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  val def_cmd: (Attrib.binding * ((binding * mixfix) * (string * string list))) list -> state -> state
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  val chain: state -> state
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  val chain_facts: thm list -> state -> state
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  val note_thmss: (Thm.binding * (thm list * attribute list) list) list -> state -> state
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  val note_thmss_cmd: (Attrib.binding * (Facts.ref * Attrib.src list) list) list -> state -> state
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  val from_thmss: ((thm list * attribute list) list) list -> state -> state
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  val from_thmss_cmd: ((Facts.ref * Attrib.src list) list) list -> state -> state
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  val with_thmss: ((thm list * attribute list) list) list -> state -> state
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  val with_thmss_cmd: ((Facts.ref * Attrib.src list) list) list -> state -> state
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  val using: ((thm list * attribute list) list) list -> state -> state
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  val using_cmd: ((Facts.ref * Attrib.src list) list) list -> state -> state
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  val unfolding: ((thm list * attribute list) list) list -> state -> state
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  val unfolding_cmd: ((Facts.ref * Attrib.src list) list) list -> state -> state
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  val invoke_case: string * binding option list * attribute list -> state -> state
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  val invoke_case_cmd: string * binding option list * Attrib.src list -> state -> state
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  val begin_block: state -> state
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  val next_block: state -> state
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  val end_block: state -> state
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  val begin_notepad: Proof.context -> state
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  val end_notepad: state -> Proof.context
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  val proof: Method.text option -> state -> state Seq.seq
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  val defer: int option -> state -> state Seq.seq
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  val prefer: int -> state -> state Seq.seq
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  val apply: Method.text -> state -> state Seq.seq
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  val apply_end: Method.text -> state -> state Seq.seq
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  val local_goal: (context -> ((string * string) * (string * thm list) list) -> unit) ->
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    (Proof.context -> 'a -> attribute) ->
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    ('b list -> context -> (term list list * (context -> context)) * context) ->
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    string -> Method.text option -> (thm list list -> state -> state) ->
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    ((binding * 'a list) * 'b) list -> state -> state
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  val local_qed: Method.text option * bool -> state -> state
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  val theorem: Method.text option -> (thm list list -> context -> context) ->
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    (term * term list) list list -> context -> state
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  val theorem_cmd: Method.text option -> (thm list list -> context -> context) ->
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    (string * string list) list list -> context -> state
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  val global_qed: Method.text option * bool -> state -> context
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  val local_terminal_proof: Method.text * Method.text option -> state -> state
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  val local_default_proof: state -> state
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  val local_immediate_proof: state -> state
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  val local_skip_proof: bool -> state -> state
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  val local_done_proof: state -> state
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  val global_terminal_proof: Method.text * Method.text option -> state -> context
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  val global_default_proof: state -> context
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  val global_immediate_proof: state -> context
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  val global_skip_proof: bool -> state -> context
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  val global_done_proof: state -> context
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  val have: Method.text option -> (thm list list -> state -> state) ->
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    (Thm.binding * (term * term list) list) list -> bool -> state -> state
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  val have_cmd: Method.text option -> (thm list list -> state -> state) ->
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    (Attrib.binding * (string * string list) list) list -> bool -> state -> state
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  val show: Method.text option -> (thm list list -> state -> state) ->
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    (Thm.binding * (term * term list) list) list -> bool -> state -> state
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  val show_cmd: Method.text option -> (thm list list -> state -> state) ->
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    (Attrib.binding * (string * string list) list) list -> bool -> state -> state
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  val begin_proofs: state -> state
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  val register_proofs: thm list -> state -> state
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  val join_recent_proofs: state -> unit
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  val schematic_goal: state -> bool
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  val local_future_proof: (state -> ('a * state) future) -> state -> 'a future * state
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  val global_future_proof: (state -> ('a * Proof.context) future) -> state -> 'a future * context
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  val local_future_terminal_proof: Method.text * Method.text option -> bool -> state -> state
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  val global_future_terminal_proof: Method.text * Method.text option -> bool -> state -> context
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end;
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structure Proof: PROOF =
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struct
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type context = Proof.context;
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type method = Method.method;
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(** proof state **)
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(* datatype state *)
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datatype mode = Forward | Chain | Backward;
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datatype state =
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  State of node Stack.T
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and node =
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  Node of
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   {context: context,
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    facts: thm list option,
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    mode: mode,
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    goal: goal option}
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and goal =
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  Goal of
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   {statement: (string * Position.T) * term list list * term,
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      (*goal kind and statement (starting with vars), initial proposition*)
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    messages: (unit -> Pretty.T) list,    (*persistent messages (hints etc.)*)
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    using: thm list,                      (*goal facts*)
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    goal: thm,                            (*subgoals ==> statement*)
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    before_qed: Method.text option,
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    after_qed:
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      (thm list list -> state -> state) *
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      (thm list list -> context -> context)};
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fun make_goal (statement, messages, using, goal, before_qed, after_qed) =
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  Goal {statement = statement, messages = messages, using = using, goal = goal,
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    before_qed = before_qed, after_qed = after_qed};
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fun make_node (context, facts, mode, goal) =
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  Node {context = context, facts = facts, mode = mode, goal = goal};
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fun map_node f (Node {context, facts, mode, goal}) =
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  make_node (f (context, facts, mode, goal));
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val init_context =
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  Proof_Context.set_stmt true #>
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  Proof_Context.map_naming (K Name_Space.local_naming);
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fun init ctxt =
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  State (Stack.init (make_node (init_context ctxt, NONE, Forward, NONE)));
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fun top (State st) = Stack.top st |> (fn Node node => node);
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fun bottom (State st) = Stack.bottom st |> (fn Node node => node);
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fun map_top f (State st) = State (Stack.map_top (map_node f) st);
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fun map_bottom f (State st) = State (Stack.map_bottom (map_node f) st);
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fun map_all f (State st) = State (Stack.map_all (map_node f) st);
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(** basic proof state operations **)
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(* block structure *)
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fun open_block (State st) = State (Stack.push st);
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fun close_block (State st) = State (Stack.pop st)
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  handle List.Empty => error "Unbalanced block parentheses";
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fun level (State st) = Stack.level st;
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fun assert_bottom b state =
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  let val b' = level state <= 2 in
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    if b andalso not b' then error "Not at bottom of proof"
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    else if not b andalso b' then error "Already at bottom of proof"
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    else state
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  end;
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(* context *)
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val context_of = #context o top;
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val theory_of = Proof_Context.theory_of o context_of;
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fun map_node_context f =
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  map_node (fn (ctxt, facts, mode, goal) => (f ctxt, facts, mode, goal));
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fun map_context f =
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  map_top (fn (ctxt, facts, mode, goal) => (f ctxt, facts, mode, goal));
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fun map_context_result f state =
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  f (context_of state) ||> (fn ctxt => map_context (K ctxt) state);
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fun map_context_bottom f =
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  map_bottom (fn (ctxt, facts, mode, goal) => (f ctxt, facts, mode, goal));
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fun map_contexts f = map_all (fn (ctxt, facts, mode, goal) => (f ctxt, facts, mode, goal));
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fun propagate_ml_env state = map_contexts
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  (Context.proof_map (ML_Env.inherit (Context.Proof (context_of state)))) state;
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val bind_terms = map_context o Proof_Context.bind_terms;
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val put_thms = map_context oo Proof_Context.put_thms;
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(* facts *)
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val get_facts = #facts o top;
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fun the_facts state =
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  (case get_facts state of SOME facts => facts
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  | NONE => error "No current facts available");
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fun the_fact state =
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  (case the_facts state of [thm] => thm
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  | _ => error "Single theorem expected");
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fun put_facts facts =
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  map_top (fn (ctxt, _, mode, goal) => (ctxt, facts, mode, goal)) #>
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  put_thms true (Auto_Bind.thisN, facts);
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val set_facts = put_facts o SOME;
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val reset_facts = put_facts NONE;
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fun these_factss more_facts (named_factss, state) =
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  (named_factss, state |> set_facts (maps snd named_factss @ more_facts));
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fun export_facts inner outer =
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  (case get_facts inner of
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    NONE => reset_facts outer
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  | SOME thms =>
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      thms
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      |> Proof_Context.export (context_of inner) (context_of outer)
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      |> (fn ths => set_facts ths outer));
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(* mode *)
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val get_mode = #mode o top;
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fun put_mode mode = map_top (fn (ctxt, facts, _, goal) => (ctxt, facts, mode, goal));
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val mode_name = (fn Forward => "state" | Chain => "chain" | Backward => "prove");
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fun assert_mode pred state =
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  let val mode = get_mode state in
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    if pred mode then state
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    else error ("Illegal application of proof command in " ^ quote (mode_name mode) ^ " mode")
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  end;
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val assert_forward = assert_mode (fn mode => mode = Forward);
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val assert_chain = assert_mode (fn mode => mode = Chain);
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val assert_forward_or_chain = assert_mode (fn mode => mode = Forward orelse mode = Chain);
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val assert_backward = assert_mode (fn mode => mode = Backward);
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val assert_no_chain = assert_mode (fn mode => mode <> Chain);
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val enter_forward = put_mode Forward;
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val enter_chain = put_mode Chain;
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val enter_backward = put_mode Backward;
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(* current goal *)
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fun current_goal state =
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  (case top state of
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    {context, goal = SOME (Goal goal), ...} => (context, goal)
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  | _ => error "No current goal");
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fun assert_current_goal g state =
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  let val g' = can current_goal state in
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    if g andalso not g' then error "No goal in this block"
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    else if not g andalso g' then error "Goal present in this block"
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    else state
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  end;
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fun put_goal goal = map_top (fn (ctxt, using, mode, _) => (ctxt, using, mode, goal));
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val set_goal = put_goal o SOME;
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val reset_goal = put_goal NONE;
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val before_qed = #before_qed o #2 o current_goal;
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(* nested goal *)
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fun map_goal f g h (State (Node {context, facts, mode, goal = SOME goal}, node :: nodes)) =
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      let
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        val Goal {statement, messages, using, goal, before_qed, after_qed} = goal;
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        val goal' = make_goal (g (statement, messages, using, goal, before_qed, after_qed));
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        val node' = map_node_context h node;
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      in State (make_node (f context, facts, mode, SOME goal'), node' :: nodes) end
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  | map_goal f g h (State (nd, node :: nodes)) =
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      let
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        val nd' = map_node_context f nd;
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        val State (node', nodes') = map_goal f g h (State (node, nodes));
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      in State (nd', node' :: nodes') end
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  | map_goal _ _ _ state = state;
wenzelm@5820
   319
wenzelm@47068
   320
fun provide_goal goal = map_goal I (fn (statement, _, using, _, before_qed, after_qed) =>
wenzelm@47431
   321
  (statement, [], using, goal, before_qed, after_qed)) I;
wenzelm@19188
   322
wenzelm@24543
   323
fun goal_message msg = map_goal I (fn (statement, messages, using, goal, before_qed, after_qed) =>
wenzelm@47431
   324
  (statement, msg :: messages, using, goal, before_qed, after_qed)) I;
wenzelm@24543
   325
wenzelm@24556
   326
fun using_facts using = map_goal I (fn (statement, _, _, goal, before_qed, after_qed) =>
wenzelm@47431
   327
  (statement, [], using, goal, before_qed, after_qed)) I;
wenzelm@17359
   328
wenzelm@17359
   329
local
wenzelm@17359
   330
  fun find i state =
wenzelm@17359
   331
    (case try current_goal state of
wenzelm@17359
   332
      SOME (ctxt, goal) => (ctxt, (i, goal))
wenzelm@18678
   333
    | NONE => find (i + 1) (close_block state handle ERROR _ => error "No goal present"));
wenzelm@17359
   334
in val find_goal = find 0 end;
wenzelm@17359
   335
wenzelm@17359
   336
fun get_goal state =
wenzelm@17359
   337
  let val (ctxt, (_, {using, goal, ...})) = find_goal state
wenzelm@17359
   338
  in (ctxt, (using, goal)) end;
wenzelm@5820
   339
wenzelm@5820
   340
wenzelm@5820
   341
wenzelm@12423
   342
(** pretty_state **)
wenzelm@5820
   343
skalberg@15531
   344
fun pretty_facts _ _ NONE = []
skalberg@15531
   345
  | pretty_facts s ctxt (SOME ths) =
wenzelm@32091
   346
      [Pretty.big_list (s ^ "this:") (map (Display.pretty_thm ctxt) ths), Pretty.str ""];
wenzelm@6756
   347
wenzelm@17359
   348
fun pretty_state nr state =
wenzelm@5820
   349
  let
wenzelm@49011
   350
    val {context = ctxt, facts, mode, goal = _} = top state;
wenzelm@42717
   351
    val verbose = Config.get ctxt Proof_Context.verbose;
wenzelm@5820
   352
wenzelm@5820
   353
    fun levels_up 0 = ""
wenzelm@17359
   354
      | levels_up 1 = "1 level up"
wenzelm@17359
   355
      | levels_up i = string_of_int i ^ " levels up";
wenzelm@5820
   356
wenzelm@11556
   357
    fun subgoals 0 = ""
wenzelm@17359
   358
      | subgoals 1 = "1 subgoal"
wenzelm@17359
   359
      | subgoals n = string_of_int n ^ " subgoals";
wenzelm@17359
   360
wenzelm@17359
   361
    fun description strs =
wenzelm@28375
   362
      (case filter_out (fn s => s = "") strs of [] => ""
wenzelm@17359
   363
      | strs' => enclose " (" ")" (commas strs'));
wenzelm@12146
   364
wenzelm@39051
   365
    fun prt_goal (SOME (_, (i,
wenzelm@29416
   366
      {statement = ((_, pos), _, _), messages, using, goal, before_qed = _, after_qed = _}))) =
wenzelm@17359
   367
          pretty_facts "using " ctxt
wenzelm@17359
   368
            (if mode <> Backward orelse null using then NONE else SOME using) @
wenzelm@21442
   369
          [Pretty.str ("goal" ^
wenzelm@21442
   370
            description [levels_up (i div 2), subgoals (Thm.nprems_of goal)] ^ ":")] @
wenzelm@39125
   371
          Goal_Display.pretty_goals ctxt goal @
wenzelm@25958
   372
          (map (fn msg => Position.setmp_thread_data pos msg ()) (rev messages))
wenzelm@17359
   373
      | prt_goal NONE = [];
wenzelm@6848
   374
wenzelm@17359
   375
    val prt_ctxt =
wenzelm@42717
   376
      if verbose orelse mode = Forward then Proof_Context.pretty_context ctxt
wenzelm@42360
   377
      else if mode = Backward then Proof_Context.pretty_ctxt ctxt
wenzelm@7575
   378
      else [];
wenzelm@17359
   379
  in
wenzelm@17359
   380
    [Pretty.str ("proof (" ^ mode_name mode ^ "): step " ^ string_of_int nr ^
wenzelm@42717
   381
      (if verbose then ", depth " ^ string_of_int (level state div 2 - 1) else "")),
wenzelm@17359
   382
      Pretty.str ""] @
wenzelm@17359
   383
    (if null prt_ctxt then [] else prt_ctxt @ [Pretty.str ""]) @
wenzelm@42717
   384
    (if verbose orelse mode = Forward then
wenzelm@39051
   385
       pretty_facts "" ctxt facts @ prt_goal (try find_goal state)
wenzelm@39051
   386
     else if mode = Chain then pretty_facts "picking " ctxt facts
wenzelm@17359
   387
     else prt_goal (try find_goal state))
wenzelm@17359
   388
  end;
wenzelm@5820
   389
wenzelm@12085
   390
fun pretty_goals main state =
wenzelm@39125
   391
  let
wenzelm@39129
   392
    val (_, (_, goal)) = get_goal state;
wenzelm@39129
   393
    val ctxt = context_of state
wenzelm@39125
   394
      |> Config.put Goal_Display.show_main_goal main
wenzelm@39125
   395
      |> Config.put Goal_Display.goals_total false;
wenzelm@39129
   396
  in Goal_Display.pretty_goals ctxt goal end;
wenzelm@10320
   397
wenzelm@5820
   398
wenzelm@5820
   399
wenzelm@5820
   400
(** proof steps **)
wenzelm@5820
   401
wenzelm@17359
   402
(* refine via method *)
wenzelm@5820
   403
wenzelm@8234
   404
local
wenzelm@8234
   405
wenzelm@16146
   406
fun goalN i = "goal" ^ string_of_int i;
wenzelm@16146
   407
fun goals st = map goalN (1 upto Thm.nprems_of st);
wenzelm@16146
   408
wenzelm@16146
   409
fun no_goal_cases st = map (rpair NONE) (goals st);
wenzelm@16146
   410
wenzelm@16146
   411
fun goal_cases st =
wenzelm@47815
   412
  Rule_Cases.make_common
wenzelm@47815
   413
    (Thm.theory_of_thm st, Thm.prop_of st) (map (rpair [] o rpair []) (goals st));
wenzelm@16146
   414
wenzelm@32193
   415
fun apply_method current_context meth state =
wenzelm@6848
   416
  let
wenzelm@24556
   417
    val (goal_ctxt, (_, {statement, messages = _, using, goal, before_qed, after_qed})) =
wenzelm@24543
   418
      find_goal state;
wenzelm@25958
   419
    val ctxt = if current_context then context_of state else goal_ctxt;
wenzelm@16146
   420
  in
wenzelm@32193
   421
    Method.apply meth ctxt using goal |> Seq.map (fn (meth_cases, goal') =>
wenzelm@6848
   422
      state
wenzelm@16146
   423
      |> map_goal
wenzelm@42360
   424
          (Proof_Context.add_cases false (no_goal_cases goal @ goal_cases goal') #>
wenzelm@42360
   425
           Proof_Context.add_cases true meth_cases)
wenzelm@47431
   426
          (K (statement, [], using, goal', before_qed, after_qed)) I)
wenzelm@16146
   427
  end;
wenzelm@5820
   428
wenzelm@19188
   429
fun select_goals n meth state =
wenzelm@19224
   430
  state
wenzelm@19224
   431
  |> (#2 o #2 o get_goal)
wenzelm@21687
   432
  |> ALLGOALS Goal.conjunction_tac
wenzelm@19224
   433
  |> Seq.maps (fn goal =>
wenzelm@19188
   434
    state
wenzelm@47068
   435
    |> Seq.lift provide_goal (Goal.extract 1 n goal |> Seq.maps (Goal.conjunction_tac 1))
wenzelm@19188
   436
    |> Seq.maps meth
wenzelm@19188
   437
    |> Seq.maps (fn state' => state'
wenzelm@47068
   438
      |> Seq.lift provide_goal (Goal.retrofit 1 n (#2 (#2 (get_goal state'))) goal))
wenzelm@32193
   439
    |> Seq.maps (apply_method true (K Method.succeed)));
wenzelm@19188
   440
wenzelm@17112
   441
fun apply_text cc text state =
wenzelm@17112
   442
  let
wenzelm@17112
   443
    val thy = theory_of state;
wenzelm@17112
   444
wenzelm@32193
   445
    fun eval (Method.Basic m) = apply_method cc m
wenzelm@32193
   446
      | eval (Method.Source src) = apply_method cc (Method.method thy src)
wenzelm@32193
   447
      | eval (Method.Source_i src) = apply_method cc (Method.method_i thy src)
wenzelm@17112
   448
      | eval (Method.Then txts) = Seq.EVERY (map eval txts)
wenzelm@17112
   449
      | eval (Method.Orelse txts) = Seq.FIRST (map eval txts)
wenzelm@17112
   450
      | eval (Method.Try txt) = Seq.TRY (eval txt)
wenzelm@19188
   451
      | eval (Method.Repeat1 txt) = Seq.REPEAT1 (eval txt)
wenzelm@19188
   452
      | eval (Method.SelectGoals (n, txt)) = select_goals n (eval txt);
wenzelm@17112
   453
  in eval text state end;
wenzelm@17112
   454
wenzelm@8234
   455
in
wenzelm@8234
   456
wenzelm@17112
   457
val refine = apply_text true;
wenzelm@17112
   458
val refine_end = apply_text false;
wenzelm@32856
   459
fun refine_insert ths = Seq.hd o refine (Method.Basic (K (Method.insert ths)));
wenzelm@18908
   460
wenzelm@8234
   461
end;
wenzelm@8234
   462
wenzelm@5820
   463
wenzelm@17359
   464
(* refine via sub-proof *)
wenzelm@17359
   465
wenzelm@46466
   466
local
wenzelm@46466
   467
wenzelm@30557
   468
fun finish_tac 0 = K all_tac
wenzelm@30557
   469
  | finish_tac n =
wenzelm@30557
   470
      Goal.norm_hhf_tac THEN'
wenzelm@30557
   471
      SUBGOAL (fn (goal, i) =>
wenzelm@30557
   472
        if can Logic.unprotect (Logic.strip_assums_concl goal) then
wenzelm@30557
   473
          Tactic.etac Drule.protectI i THEN finish_tac (n - 1) i
wenzelm@30557
   474
        else finish_tac (n - 1) (i + 1));
wenzelm@30557
   475
wenzelm@20208
   476
fun goal_tac rule =
wenzelm@30557
   477
  Goal.norm_hhf_tac THEN'
wenzelm@30557
   478
  Tactic.rtac rule THEN'
wenzelm@30557
   479
  finish_tac (Thm.nprems_of rule);
wenzelm@11816
   480
wenzelm@46466
   481
fun FINDGOAL tac st =
wenzelm@46466
   482
  let fun find i n = if i > n then Seq.fail else Seq.APPEND (tac i, find (i + 1) n)
wenzelm@46466
   483
  in find 1 (Thm.nprems_of st) st end;
wenzelm@46466
   484
wenzelm@46466
   485
in
wenzelm@46466
   486
wenzelm@19915
   487
fun refine_goals print_rule inner raw_rules state =
wenzelm@19915
   488
  let
wenzelm@19915
   489
    val (outer, (_, goal)) = get_goal state;
wenzelm@20208
   490
    fun refine rule st = (print_rule outer rule; FINDGOAL (goal_tac rule) st);
wenzelm@19915
   491
  in
wenzelm@19915
   492
    raw_rules
wenzelm@42360
   493
    |> Proof_Context.goal_export inner outer
wenzelm@47068
   494
    |> (fn rules => Seq.lift provide_goal (EVERY (map refine rules) goal) state)
wenzelm@19915
   495
  end;
wenzelm@17359
   496
wenzelm@46466
   497
end;
wenzelm@46466
   498
wenzelm@6932
   499
wenzelm@17359
   500
(* conclude_goal *)
wenzelm@6932
   501
wenzelm@28627
   502
fun conclude_goal ctxt goal propss =
wenzelm@5820
   503
  let
wenzelm@42360
   504
    val thy = Proof_Context.theory_of ctxt;
wenzelm@24920
   505
    val string_of_term = Syntax.string_of_term ctxt;
wenzelm@32091
   506
    val string_of_thm = Display.string_of_thm ctxt;
wenzelm@5820
   507
wenzelm@17359
   508
    val ngoals = Thm.nprems_of goal;
wenzelm@19774
   509
    val _ = ngoals = 0 orelse error (Pretty.string_of (Pretty.chunks
wenzelm@39125
   510
      (Goal_Display.pretty_goals ctxt goal @
wenzelm@47065
   511
        [Pretty.str (string_of_int ngoals ^ " unsolved goal(s)")])));
wenzelm@20224
   512
wenzelm@20224
   513
    val extra_hyps = Assumption.extra_hyps ctxt goal;
wenzelm@20224
   514
    val _ = null extra_hyps orelse
wenzelm@20224
   515
      error ("Additional hypotheses:\n" ^ cat_lines (map string_of_term extra_hyps));
wenzelm@5820
   516
wenzelm@23418
   517
    fun lost_structure () = error ("Lost goal structure:\n" ^ string_of_thm goal);
wenzelm@23418
   518
berghofe@23782
   519
    val th = Goal.conclude
wenzelm@23806
   520
      (if length (flat propss) > 1 then Thm.norm_proof goal else goal)
berghofe@23782
   521
      handle THM _ => lost_structure ();
wenzelm@23418
   522
    val goal_propss = filter_out null propss;
wenzelm@23418
   523
    val results =
wenzelm@23418
   524
      Conjunction.elim_balanced (length goal_propss) th
wenzelm@23418
   525
      |> map2 Conjunction.elim_balanced (map length goal_propss)
wenzelm@23418
   526
      handle THM _ => lost_structure ();
wenzelm@23418
   527
    val _ = Unify.matches_list thy (flat goal_propss) (map Thm.prop_of (flat results)) orelse
wenzelm@19774
   528
      error ("Proved a different theorem:\n" ^ string_of_thm th);
wenzelm@28627
   529
    val _ = Thm.check_shyps (Variable.sorts_of ctxt) th;
wenzelm@23418
   530
wenzelm@23418
   531
    fun recover_result ([] :: pss) thss = [] :: recover_result pss thss
wenzelm@23418
   532
      | recover_result (_ :: pss) (ths :: thss) = ths :: recover_result pss thss
wenzelm@23418
   533
      | recover_result [] [] = []
wenzelm@23418
   534
      | recover_result _ _ = lost_structure ();
wenzelm@23418
   535
  in recover_result propss results end;
wenzelm@5820
   536
wenzelm@5820
   537
wenzelm@33288
   538
(* goal views -- corresponding to methods *)
wenzelm@33288
   539
wenzelm@33288
   540
fun raw_goal state =
wenzelm@33288
   541
  let val (ctxt, (facts, goal)) = get_goal state
wenzelm@33288
   542
  in {context = ctxt, facts = facts, goal = goal} end;
wenzelm@33288
   543
wenzelm@33288
   544
val goal = raw_goal o refine_insert [];
wenzelm@33288
   545
wenzelm@33288
   546
fun simple_goal state =
wenzelm@33288
   547
  let
wenzelm@33288
   548
    val (_, (facts, _)) = get_goal state;
wenzelm@33288
   549
    val (ctxt, (_, goal)) = get_goal (refine_insert facts state);
wenzelm@33288
   550
  in {context = ctxt, goal = goal} end;
wenzelm@33288
   551
wenzelm@38721
   552
fun status_markup state =
wenzelm@38721
   553
  (case try goal state of
wenzelm@45666
   554
    SOME {goal, ...} => Isabelle_Markup.proof_state (Thm.nprems_of goal)
wenzelm@38721
   555
  | NONE => Markup.empty);
wenzelm@38721
   556
wenzelm@33288
   557
wenzelm@5820
   558
wenzelm@5820
   559
(*** structured proof commands ***)
wenzelm@5820
   560
wenzelm@17112
   561
(** context elements **)
wenzelm@5820
   562
wenzelm@36324
   563
(* let bindings *)
wenzelm@5820
   564
wenzelm@16813
   565
local
wenzelm@16813
   566
wenzelm@17359
   567
fun gen_bind bind args state =
wenzelm@5820
   568
  state
wenzelm@5820
   569
  |> assert_forward
wenzelm@36324
   570
  |> map_context (bind true args #> snd)
wenzelm@47068
   571
  |> reset_facts;
wenzelm@5820
   572
wenzelm@16813
   573
in
wenzelm@16813
   574
wenzelm@42360
   575
val let_bind = gen_bind Proof_Context.match_bind_i;
wenzelm@42360
   576
val let_bind_cmd = gen_bind Proof_Context.match_bind;
wenzelm@5820
   577
wenzelm@16813
   578
end;
wenzelm@16813
   579
wenzelm@5820
   580
wenzelm@36505
   581
(* concrete syntax *)
wenzelm@36505
   582
wenzelm@36505
   583
local
wenzelm@36505
   584
wenzelm@36507
   585
fun gen_write prep_arg mode args =
wenzelm@36507
   586
  assert_forward
wenzelm@42360
   587
  #> map_context (fn ctxt => ctxt |> Proof_Context.notation true mode (map (prep_arg ctxt) args))
wenzelm@47068
   588
  #> reset_facts;
wenzelm@36505
   589
wenzelm@36505
   590
in
wenzelm@36505
   591
wenzelm@36505
   592
val write = gen_write (K I);
wenzelm@36505
   593
wenzelm@36505
   594
val write_cmd =
wenzelm@36505
   595
  gen_write (fn ctxt => fn (c, mx) =>
wenzelm@42360
   596
    (Proof_Context.read_const ctxt false (Mixfix.mixfixT mx) c, mx));
wenzelm@36505
   597
wenzelm@36505
   598
end;
wenzelm@36505
   599
wenzelm@36505
   600
wenzelm@17359
   601
(* fix *)
wenzelm@9196
   602
wenzelm@12714
   603
local
wenzelm@12714
   604
wenzelm@30763
   605
fun gen_fix prep_vars args =
wenzelm@17359
   606
  assert_forward
wenzelm@45597
   607
  #> map_context (fn ctxt => snd (Proof_Context.add_fixes (fst (prep_vars args ctxt)) ctxt))
wenzelm@47068
   608
  #> reset_facts;
wenzelm@5820
   609
wenzelm@16813
   610
in
wenzelm@16813
   611
wenzelm@45597
   612
val fix = gen_fix Proof_Context.cert_vars;
wenzelm@45597
   613
val fix_cmd = gen_fix Proof_Context.read_vars;
wenzelm@5820
   614
wenzelm@16813
   615
end;
wenzelm@16813
   616
wenzelm@5820
   617
wenzelm@17359
   618
(* assume etc. *)
wenzelm@5820
   619
wenzelm@16813
   620
local
wenzelm@16813
   621
wenzelm@17112
   622
fun gen_assume asm prep_att exp args state =
wenzelm@5820
   623
  state
wenzelm@5820
   624
  |> assert_forward
wenzelm@47815
   625
  |> map_context_result (asm exp (Attrib.map_specs (map (prep_att (context_of state))) args))
wenzelm@17359
   626
  |> these_factss [] |> #2;
wenzelm@6932
   627
wenzelm@16813
   628
in
wenzelm@16813
   629
wenzelm@42360
   630
val assm = gen_assume Proof_Context.add_assms_i (K I);
wenzelm@47815
   631
val assm_cmd = gen_assume Proof_Context.add_assms Attrib.attribute_cmd;
wenzelm@36323
   632
val assume = assm Assumption.assume_export;
wenzelm@36323
   633
val assume_cmd = assm_cmd Assumption.assume_export;
wenzelm@36323
   634
val presume = assm Assumption.presume_export;
wenzelm@36323
   635
val presume_cmd = assm_cmd Assumption.presume_export;
wenzelm@5820
   636
wenzelm@16813
   637
end;
wenzelm@16813
   638
wenzelm@7271
   639
wenzelm@17359
   640
(* def *)
wenzelm@11891
   641
wenzelm@16813
   642
local
wenzelm@16813
   643
wenzelm@20913
   644
fun gen_def prep_att prep_vars prep_binds args state =
wenzelm@11891
   645
  let
wenzelm@11891
   646
    val _ = assert_forward state;
wenzelm@20913
   647
    val (raw_name_atts, (raw_vars, raw_rhss)) = args |> split_list ||> split_list;
wenzelm@47815
   648
    val name_atts = map (apsnd (map (prep_att (context_of state)))) raw_name_atts;
wenzelm@11891
   649
  in
wenzelm@20913
   650
    state
wenzelm@20913
   651
    |> map_context_result (prep_vars (map (fn (x, mx) => (x, NONE, mx)) raw_vars))
wenzelm@20913
   652
    |>> map (fn (x, _, mx) => (x, mx))
wenzelm@20913
   653
    |-> (fn vars =>
wenzelm@20913
   654
      map_context_result (prep_binds false (map swap raw_rhss))
wenzelm@35624
   655
      #-> (fn rhss => map_context_result (Local_Defs.add_defs (vars ~~ (name_atts ~~ rhss)))))
wenzelm@47068
   656
    |-> (set_facts o map (#2 o #2))
wenzelm@11891
   657
  end;
wenzelm@11891
   658
wenzelm@16813
   659
in
wenzelm@16813
   660
wenzelm@42360
   661
val def = gen_def (K I) Proof_Context.cert_vars Proof_Context.match_bind_i;
wenzelm@47815
   662
val def_cmd = gen_def Attrib.attribute_cmd Proof_Context.read_vars Proof_Context.match_bind;
wenzelm@11891
   663
wenzelm@16813
   664
end;
wenzelm@16813
   665
wenzelm@11891
   666
wenzelm@8374
   667
wenzelm@17112
   668
(** facts **)
wenzelm@5820
   669
wenzelm@17359
   670
(* chain *)
wenzelm@5820
   671
wenzelm@24011
   672
fun clean_facts ctxt =
wenzelm@47068
   673
  set_facts (filter_out Thm.is_dummy (the_facts ctxt)) ctxt;
wenzelm@24011
   674
wenzelm@17359
   675
val chain =
wenzelm@17359
   676
  assert_forward
wenzelm@24011
   677
  #> clean_facts
wenzelm@17359
   678
  #> enter_chain;
wenzelm@5820
   679
wenzelm@17359
   680
fun chain_facts facts =
wenzelm@47068
   681
  set_facts facts
wenzelm@17359
   682
  #> chain;
wenzelm@5820
   683
wenzelm@5820
   684
wenzelm@17359
   685
(* note etc. *)
wenzelm@17112
   686
haftmann@28965
   687
fun no_binding args = map (pair (Binding.empty, [])) args;
wenzelm@17112
   688
wenzelm@17112
   689
local
wenzelm@17112
   690
wenzelm@30760
   691
fun gen_thmss more_facts opt_chain opt_result prep_atts prep_fact args state =
wenzelm@17112
   692
  state
wenzelm@17112
   693
  |> assert_forward
wenzelm@47815
   694
  |> map_context_result (fn ctxt => ctxt |> Proof_Context.note_thmss ""
wenzelm@47815
   695
    (Attrib.map_facts_refs (map (prep_atts ctxt)) (prep_fact ctxt) args))
wenzelm@17112
   696
  |> these_factss (more_facts state)
wenzelm@17359
   697
  ||> opt_chain
wenzelm@17359
   698
  |> opt_result;
wenzelm@17112
   699
wenzelm@17112
   700
in
wenzelm@17112
   701
wenzelm@36323
   702
val note_thmss = gen_thmss (K []) I #2 (K I) (K I);
wenzelm@47815
   703
val note_thmss_cmd = gen_thmss (K []) I #2 Attrib.attribute_cmd Proof_Context.get_fact;
wenzelm@17112
   704
wenzelm@36323
   705
val from_thmss = gen_thmss (K []) chain #2 (K I) (K I) o no_binding;
wenzelm@47815
   706
val from_thmss_cmd =
wenzelm@47815
   707
  gen_thmss (K []) chain #2 Attrib.attribute_cmd Proof_Context.get_fact o no_binding;
wenzelm@17359
   708
wenzelm@36323
   709
val with_thmss = gen_thmss the_facts chain #2 (K I) (K I) o no_binding;
wenzelm@47815
   710
val with_thmss_cmd =
wenzelm@47815
   711
  gen_thmss the_facts chain #2 Attrib.attribute_cmd Proof_Context.get_fact o no_binding;
wenzelm@30760
   712
wenzelm@30760
   713
val local_results = gen_thmss (K []) I I (K I) (K I) o map (apsnd Thm.simple_fact);
wenzelm@17359
   714
wenzelm@17112
   715
end;
wenzelm@17112
   716
wenzelm@17112
   717
wenzelm@18548
   718
(* using/unfolding *)
wenzelm@17112
   719
wenzelm@17112
   720
local
wenzelm@17112
   721
wenzelm@45390
   722
fun gen_using f g prep_att prep_fact args state =
wenzelm@17112
   723
  state
wenzelm@17112
   724
  |> assert_backward
wenzelm@21442
   725
  |> map_context_result
wenzelm@47815
   726
    (fn ctxt => ctxt |> Proof_Context.note_thmss ""
wenzelm@47815
   727
      (Attrib.map_facts_refs (map (prep_att ctxt)) (prep_fact ctxt) (no_binding args)))
wenzelm@18843
   728
  |> (fn (named_facts, state') =>
wenzelm@24556
   729
    state' |> map_goal I (fn (statement, _, using, goal, before_qed, after_qed) =>
wenzelm@18843
   730
      let
wenzelm@18843
   731
        val ctxt = context_of state';
wenzelm@19482
   732
        val ths = maps snd named_facts;
wenzelm@47431
   733
      in (statement, [], f ctxt ths using, g ctxt ths goal, before_qed, after_qed) end) I);
wenzelm@18548
   734
wenzelm@24050
   735
fun append_using _ ths using = using @ filter_out Thm.is_dummy ths;
wenzelm@35624
   736
fun unfold_using ctxt ths = map (Local_Defs.unfold ctxt ths);
wenzelm@35624
   737
val unfold_goals = Local_Defs.unfold_goals;
wenzelm@17112
   738
wenzelm@17112
   739
in
wenzelm@17112
   740
wenzelm@36323
   741
val using = gen_using append_using (K (K I)) (K I) (K I);
wenzelm@47815
   742
val using_cmd = gen_using append_using (K (K I)) Attrib.attribute_cmd Proof_Context.get_fact;
wenzelm@36323
   743
val unfolding = gen_using unfold_using unfold_goals (K I) (K I);
wenzelm@47815
   744
val unfolding_cmd = gen_using unfold_using unfold_goals Attrib.attribute_cmd Proof_Context.get_fact;
wenzelm@17112
   745
wenzelm@17112
   746
end;
wenzelm@17112
   747
wenzelm@17112
   748
wenzelm@17112
   749
(* case *)
wenzelm@17112
   750
wenzelm@17112
   751
local
wenzelm@17112
   752
wenzelm@30419
   753
fun qualified_binding a =
wenzelm@30419
   754
  Binding.qualify true (Long_Name.qualifier a) (Binding.name (Long_Name.base_name a));
wenzelm@30419
   755
wenzelm@17112
   756
fun gen_invoke_case prep_att (name, xs, raw_atts) state =
wenzelm@17112
   757
  let
wenzelm@47815
   758
    val atts = map (prep_att (context_of state)) raw_atts;
wenzelm@19078
   759
    val (asms, state') = state |> map_context_result (fn ctxt =>
wenzelm@42360
   760
      ctxt |> Proof_Context.apply_case (Proof_Context.get_case ctxt name xs));
wenzelm@30419
   761
    val assumptions = asms |> map (fn (a, ts) => ((qualified_binding a, atts), map (rpair []) ts));
wenzelm@17112
   762
  in
wenzelm@17112
   763
    state'
wenzelm@36323
   764
    |> assume assumptions
wenzelm@33386
   765
    |> bind_terms Auto_Bind.no_facts
wenzelm@36323
   766
    |> `the_facts |-> (fn thms => note_thmss [((Binding.name name, []), [(thms, [])])])
wenzelm@17112
   767
  end;
wenzelm@17112
   768
wenzelm@17112
   769
in
wenzelm@17112
   770
wenzelm@36323
   771
val invoke_case = gen_invoke_case (K I);
wenzelm@47815
   772
val invoke_case_cmd = gen_invoke_case Attrib.attribute_cmd;
wenzelm@17112
   773
wenzelm@17112
   774
end;
wenzelm@17112
   775
wenzelm@17112
   776
wenzelm@17112
   777
wenzelm@17359
   778
(** proof structure **)
wenzelm@17359
   779
wenzelm@17359
   780
(* blocks *)
wenzelm@17359
   781
wenzelm@17359
   782
val begin_block =
wenzelm@17359
   783
  assert_forward
wenzelm@17359
   784
  #> open_block
wenzelm@47068
   785
  #> reset_goal
wenzelm@17359
   786
  #> open_block;
wenzelm@17359
   787
wenzelm@17359
   788
val next_block =
wenzelm@17359
   789
  assert_forward
wenzelm@17359
   790
  #> close_block
wenzelm@17359
   791
  #> open_block
wenzelm@47068
   792
  #> reset_goal
wenzelm@47068
   793
  #> reset_facts;
wenzelm@17359
   794
wenzelm@17359
   795
fun end_block state =
wenzelm@17359
   796
  state
wenzelm@17359
   797
  |> assert_forward
wenzelm@40960
   798
  |> assert_bottom false
wenzelm@17359
   799
  |> close_block
wenzelm@17359
   800
  |> assert_current_goal false
wenzelm@17359
   801
  |> close_block
wenzelm@17359
   802
  |> export_facts state;
wenzelm@17359
   803
wenzelm@17359
   804
wenzelm@40960
   805
(* global notepad *)
wenzelm@40960
   806
wenzelm@40960
   807
val begin_notepad =
wenzelm@40960
   808
  init
wenzelm@40960
   809
  #> open_block
wenzelm@40960
   810
  #> map_context (Variable.set_body true)
wenzelm@40960
   811
  #> open_block;
wenzelm@40960
   812
wenzelm@40960
   813
val end_notepad =
wenzelm@40960
   814
  assert_forward
wenzelm@40960
   815
  #> assert_bottom true
wenzelm@40960
   816
  #> close_block
wenzelm@40960
   817
  #> assert_current_goal false
wenzelm@40960
   818
  #> close_block
wenzelm@40960
   819
  #> context_of;
wenzelm@40960
   820
wenzelm@40960
   821
wenzelm@17359
   822
(* sub-proofs *)
wenzelm@17359
   823
wenzelm@17359
   824
fun proof opt_text =
wenzelm@17359
   825
  assert_backward
wenzelm@17859
   826
  #> refine (the_default Method.default_text opt_text)
wenzelm@17359
   827
  #> Seq.map (using_facts [] #> enter_forward);
wenzelm@17359
   828
wenzelm@23360
   829
fun end_proof bot txt state =
wenzelm@23360
   830
  state
wenzelm@23360
   831
  |> assert_forward
wenzelm@23360
   832
  |> assert_bottom bot
wenzelm@23360
   833
  |> close_block
wenzelm@23360
   834
  |> assert_current_goal true
wenzelm@23360
   835
  |> using_facts []
wenzelm@23360
   836
  |> `before_qed |-> (refine o the_default Method.succeed_text)
wenzelm@32193
   837
  |> Seq.maps (refine (Method.finish_text txt));
wenzelm@17359
   838
wenzelm@29383
   839
fun check_result msg sq =
wenzelm@29383
   840
  (case Seq.pull sq of
wenzelm@29383
   841
    NONE => error msg
wenzelm@29383
   842
  | SOME (s, _) => s);
wenzelm@29383
   843
wenzelm@29383
   844
fun check_finish sq = check_result "Failed to finish proof" sq;
wenzelm@29383
   845
wenzelm@17359
   846
wenzelm@17359
   847
(* unstructured refinement *)
wenzelm@17359
   848
wenzelm@32193
   849
fun defer i = assert_no_chain #> refine (Method.Basic (K (Method.defer i)));
wenzelm@32193
   850
fun prefer i = assert_no_chain #> refine (Method.Basic (K (Method.prefer i)));
wenzelm@17359
   851
wenzelm@17359
   852
fun apply text = assert_backward #> refine text #> Seq.map (using_facts []);
wenzelm@17359
   853
fun apply_end text = assert_forward #> refine_end text;
wenzelm@17359
   854
wenzelm@17359
   855
wenzelm@17359
   856
wenzelm@17112
   857
(** goals **)
wenzelm@17112
   858
wenzelm@17359
   859
(* generic goals *)
wenzelm@17359
   860
wenzelm@19774
   861
local
wenzelm@19774
   862
wenzelm@36322
   863
val is_var =
wenzelm@36322
   864
  can (dest_TVar o Logic.dest_type o Logic.dest_term) orf
wenzelm@36322
   865
  can (dest_Var o Logic.dest_term);
wenzelm@36322
   866
wenzelm@36322
   867
fun implicit_vars props =
wenzelm@19846
   868
  let
wenzelm@36354
   869
    val (var_props, _) = take_prefix is_var props;
wenzelm@36322
   870
    val explicit_vars = fold Term.add_vars var_props [];
wenzelm@36322
   871
    val vars = filter_out (member (op =) explicit_vars) (fold Term.add_vars props []);
wenzelm@36322
   872
  in map (Logic.mk_term o Var) vars end;
wenzelm@19774
   873
wenzelm@19774
   874
fun refine_terms n =
wenzelm@30510
   875
  refine (Method.Basic (K (RAW_METHOD
wenzelm@19774
   876
    (K (HEADGOAL (PRECISE_CONJUNCTS n
wenzelm@32193
   877
      (HEADGOAL (CONJUNCTS (ALLGOALS (rtac Drule.termI))))))))))
wenzelm@19774
   878
  #> Seq.hd;
wenzelm@19774
   879
wenzelm@19774
   880
in
wenzelm@17359
   881
wenzelm@17859
   882
fun generic_goal prepp kind before_qed after_qed raw_propp state =
wenzelm@5820
   883
  let
wenzelm@17359
   884
    val thy = theory_of state;
wenzelm@23418
   885
    val cert = Thm.cterm_of thy;
wenzelm@17359
   886
    val chaining = can assert_chain state;
wenzelm@25958
   887
    val pos = Position.thread_data ();
wenzelm@17359
   888
wenzelm@17359
   889
    val ((propss, after_ctxt), goal_state) =
wenzelm@5936
   890
      state
wenzelm@5936
   891
      |> assert_forward_or_chain
wenzelm@5936
   892
      |> enter_forward
wenzelm@17359
   893
      |> open_block
wenzelm@45327
   894
      |> map_context_result (prepp raw_propp);
wenzelm@19482
   895
    val props = flat propss;
wenzelm@15703
   896
wenzelm@36322
   897
    val vars = implicit_vars props;
wenzelm@36322
   898
    val propss' = vars :: propss;
wenzelm@23418
   899
    val goal_propss = filter_out null propss';
wenzelm@29346
   900
    val goal =
wenzelm@29346
   901
      cert (Logic.mk_conjunction_balanced (map Logic.mk_conjunction_balanced goal_propss))
wenzelm@28627
   902
      |> Thm.weaken_sorts (Variable.sorts_of (context_of goal_state));
wenzelm@29346
   903
    val statement = ((kind, pos), propss', Thm.term_of goal);
wenzelm@18124
   904
    val after_qed' = after_qed |>> (fn after_local =>
wenzelm@18124
   905
      fn results => map_context after_ctxt #> after_local results);
wenzelm@5820
   906
  in
wenzelm@17359
   907
    goal_state
wenzelm@21727
   908
    |> map_context (init_context #> Variable.set_body true)
wenzelm@47068
   909
    |> set_goal (make_goal (statement, [], [], Goal.init goal, before_qed, after_qed'))
wenzelm@42360
   910
    |> map_context (Proof_Context.auto_bind_goal props)
wenzelm@21565
   911
    |> chaining ? (`the_facts #-> using_facts)
wenzelm@47068
   912
    |> reset_facts
wenzelm@17359
   913
    |> open_block
wenzelm@47068
   914
    |> reset_goal
wenzelm@5820
   915
    |> enter_backward
wenzelm@23418
   916
    |> not (null vars) ? refine_terms (length goal_propss)
wenzelm@32193
   917
    |> null props ? (refine (Method.Basic Method.assumption) #> Seq.hd)
wenzelm@5820
   918
  end;
wenzelm@5820
   919
wenzelm@29090
   920
fun generic_qed after_ctxt state =
wenzelm@12503
   921
  let
wenzelm@36354
   922
    val (goal_ctxt, {statement = (_, stmt, _), goal, after_qed, ...}) = current_goal state;
wenzelm@8617
   923
    val outer_state = state |> close_block;
wenzelm@8617
   924
    val outer_ctxt = context_of outer_state;
wenzelm@8617
   925
wenzelm@18503
   926
    val props =
wenzelm@19774
   927
      flat (tl stmt)
wenzelm@19915
   928
      |> Variable.exportT_terms goal_ctxt outer_ctxt;
wenzelm@17359
   929
    val results =
wenzelm@28627
   930
      tl (conclude_goal goal_ctxt goal stmt)
wenzelm@42360
   931
      |> burrow (Proof_Context.export goal_ctxt outer_ctxt);
wenzelm@17359
   932
  in
wenzelm@17359
   933
    outer_state
wenzelm@29090
   934
    |> map_context (after_ctxt props)
wenzelm@34239
   935
    |> pair (after_qed, results)
wenzelm@17359
   936
  end;
wenzelm@17359
   937
wenzelm@19774
   938
end;
wenzelm@19774
   939
wenzelm@9469
   940
wenzelm@17359
   941
(* local goals *)
wenzelm@17359
   942
wenzelm@17859
   943
fun local_goal print_results prep_att prepp kind before_qed after_qed stmt state =
wenzelm@17359
   944
  let
wenzelm@21362
   945
    val ((names, attss), propp) =
wenzelm@47815
   946
      Attrib.map_specs (map (prep_att (context_of state))) stmt |> split_list |>> split_list;
wenzelm@17359
   947
wenzelm@18124
   948
    fun after_qed' results =
wenzelm@18808
   949
      local_results ((names ~~ attss) ~~ results)
wenzelm@17359
   950
      #-> (fn res => tap (fn st => print_results (context_of st) ((kind, ""), res) : unit))
wenzelm@18124
   951
      #> after_qed results;
wenzelm@5820
   952
  in
wenzelm@17359
   953
    state
wenzelm@21362
   954
    |> generic_goal prepp kind before_qed (after_qed', K I) propp
wenzelm@19900
   955
    |> tap (Variable.warn_extra_tfrees (context_of state) o context_of)
wenzelm@5820
   956
  end;
wenzelm@5820
   957
wenzelm@29383
   958
fun local_qeds txt =
wenzelm@29383
   959
  end_proof false txt
wenzelm@42360
   960
  #> Seq.map (generic_qed Proof_Context.auto_bind_facts #->
wenzelm@29090
   961
    (fn ((after_qed, _), results) => after_qed results));
wenzelm@5820
   962
wenzelm@29383
   963
fun local_qed txt = local_qeds txt #> check_finish;
wenzelm@29383
   964
wenzelm@5820
   965
wenzelm@17359
   966
(* global goals *)
wenzelm@17359
   967
wenzelm@45327
   968
fun prepp_auto_fixes prepp args =
wenzelm@45327
   969
  prepp args #>
wenzelm@45327
   970
  (fn ((propss, a), ctxt) => ((propss, a), (fold o fold) Variable.auto_fixes propss ctxt));
wenzelm@45327
   971
wenzelm@45327
   972
fun global_goal prepp before_qed after_qed propp =
wenzelm@45327
   973
  init #>
wenzelm@45327
   974
  generic_goal (prepp_auto_fixes prepp) "" before_qed (K I, after_qed) propp;
wenzelm@17359
   975
wenzelm@42360
   976
val theorem = global_goal Proof_Context.bind_propp_schematic_i;
wenzelm@42360
   977
val theorem_cmd = global_goal Proof_Context.bind_propp_schematic;
wenzelm@12065
   978
wenzelm@17359
   979
fun global_qeds txt =
wenzelm@17359
   980
  end_proof true txt
wenzelm@29090
   981
  #> Seq.map (generic_qed (K I) #> (fn (((_, after_qed), results), state) =>
wenzelm@29383
   982
    after_qed results (context_of state)));
wenzelm@17112
   983
wenzelm@29383
   984
fun global_qed txt = global_qeds txt #> check_finish;
wenzelm@12959
   985
wenzelm@5820
   986
wenzelm@17359
   987
(* concluding steps *)
wenzelm@17112
   988
wenzelm@29383
   989
fun terminal_proof qed initial terminal =
wenzelm@29383
   990
  proof (SOME initial) #> Seq.maps (qed terminal) #> check_finish;
wenzelm@17112
   991
wenzelm@29383
   992
fun local_terminal_proof (text, opt_text) = terminal_proof local_qeds text (opt_text, true);
wenzelm@17112
   993
val local_default_proof = local_terminal_proof (Method.default_text, NONE);
wenzelm@17112
   994
val local_immediate_proof = local_terminal_proof (Method.this_text, NONE);
wenzelm@17359
   995
fun local_skip_proof int = local_terminal_proof (Method.sorry_text int, NONE);
wenzelm@29383
   996
val local_done_proof = terminal_proof local_qeds Method.done_text (NONE, false);
wenzelm@17112
   997
wenzelm@29383
   998
fun global_terminal_proof (text, opt_text) = terminal_proof global_qeds text (opt_text, true);
wenzelm@17112
   999
val global_default_proof = global_terminal_proof (Method.default_text, NONE);
wenzelm@17112
  1000
val global_immediate_proof = global_terminal_proof (Method.this_text, NONE);
wenzelm@17359
  1001
fun global_skip_proof int = global_terminal_proof (Method.sorry_text int, NONE);
wenzelm@29383
  1002
val global_done_proof = terminal_proof global_qeds Method.done_text (NONE, false);
wenzelm@5820
  1003
wenzelm@6896
  1004
wenzelm@17359
  1005
(* common goal statements *)
wenzelm@17359
  1006
wenzelm@17359
  1007
local
wenzelm@17359
  1008
wenzelm@17859
  1009
fun gen_have prep_att prepp before_qed after_qed stmt int =
wenzelm@46728
  1010
  local_goal (Proof_Display.print_results Isabelle_Markup.state int)
wenzelm@46728
  1011
    prep_att prepp "have" before_qed after_qed stmt;
wenzelm@6896
  1012
wenzelm@17859
  1013
fun gen_show prep_att prepp before_qed after_qed stmt int state =
wenzelm@17359
  1014
  let
wenzelm@32738
  1015
    val testing = Unsynchronized.ref false;
wenzelm@32738
  1016
    val rule = Unsynchronized.ref (NONE: thm option);
wenzelm@17359
  1017
    fun fail_msg ctxt =
wenzelm@29383
  1018
      "Local statement will fail to refine any pending goal" ::
wenzelm@33389
  1019
      (case ! rule of NONE => [] | SOME th => [Proof_Display.string_of_rule ctxt "Failed" th])
wenzelm@17359
  1020
      |> cat_lines;
wenzelm@6896
  1021
wenzelm@17359
  1022
    fun print_results ctxt res =
wenzelm@46728
  1023
      if ! testing then ()
wenzelm@46728
  1024
      else Proof_Display.print_results Isabelle_Markup.state int ctxt res;
wenzelm@17359
  1025
    fun print_rule ctxt th =
wenzelm@17359
  1026
      if ! testing then rule := SOME th
wenzelm@41181
  1027
      else if int then
wenzelm@45666
  1028
        writeln
wenzelm@45666
  1029
          (Markup.markup Isabelle_Markup.state (Proof_Display.string_of_rule ctxt "Successful" th))
wenzelm@17359
  1030
      else ();
wenzelm@17359
  1031
    val test_proof =
wenzelm@29383
  1032
      try (local_skip_proof true)
wenzelm@39616
  1033
      |> Unsynchronized.setmp testing true
wenzelm@42042
  1034
      |> Exn.interruptible_capture;
wenzelm@6896
  1035
wenzelm@18124
  1036
    fun after_qed' results =
wenzelm@19482
  1037
      refine_goals print_rule (context_of state) (flat results)
wenzelm@29383
  1038
      #> check_result "Failed to refine any pending goal"
wenzelm@29383
  1039
      #> after_qed results;
wenzelm@17359
  1040
  in
wenzelm@17359
  1041
    state
wenzelm@17859
  1042
    |> local_goal print_results prep_att prepp "show" before_qed after_qed' stmt
wenzelm@21565
  1043
    |> int ? (fn goal_state =>
wenzelm@17359
  1044
      (case test_proof goal_state of
wenzelm@43761
  1045
        Exn.Res (SOME _) => goal_state
wenzelm@43761
  1046
      | Exn.Res NONE => error (fail_msg (context_of goal_state))
wenzelm@42042
  1047
      | Exn.Exn exn => raise Exn.EXCEPTIONS ([exn, ERROR (fail_msg (context_of goal_state))])))
wenzelm@17359
  1048
  end;
wenzelm@17359
  1049
wenzelm@17359
  1050
in
wenzelm@17359
  1051
wenzelm@42360
  1052
val have = gen_have (K I) Proof_Context.bind_propp_i;
wenzelm@47815
  1053
val have_cmd = gen_have Attrib.attribute_cmd Proof_Context.bind_propp;
wenzelm@42360
  1054
val show = gen_show (K I) Proof_Context.bind_propp_i;
wenzelm@47815
  1055
val show_cmd = gen_show Attrib.attribute_cmd Proof_Context.bind_propp;
wenzelm@6896
  1056
wenzelm@5820
  1057
end;
wenzelm@17359
  1058
wenzelm@28410
  1059
wenzelm@29385
  1060
wenzelm@29385
  1061
(** future proofs **)
wenzelm@29385
  1062
wenzelm@49011
  1063
(* forked proofs *)
wenzelm@49011
  1064
wenzelm@49011
  1065
val begin_proofs = map_context_bottom (Context.proof_map Thm.begin_proofs);
wenzelm@49011
  1066
val register_proofs = map_context_bottom o Context.proof_map o Thm.register_proofs;
wenzelm@49011
  1067
wenzelm@49011
  1068
val join_recent_proofs = Thm.join_local_proofs o #context o bottom;
wenzelm@49011
  1069
wenzelm@49011
  1070
wenzelm@29385
  1071
(* relevant proof states *)
wenzelm@29385
  1072
wenzelm@29385
  1073
fun is_schematic t =
wenzelm@29385
  1074
  Term.exists_subterm Term.is_Var t orelse
wenzelm@29385
  1075
  Term.exists_type (Term.exists_subtype Term.is_TVar) t;
wenzelm@29385
  1076
wenzelm@29385
  1077
fun schematic_goal state =
wenzelm@29385
  1078
  let val (_, (_, {statement = (_, _, prop), ...})) = find_goal state
wenzelm@29385
  1079
  in is_schematic prop end;
wenzelm@29385
  1080
wenzelm@29385
  1081
fun is_relevant state =
wenzelm@29385
  1082
  (case try find_goal state of
wenzelm@29385
  1083
    NONE => true
wenzelm@29385
  1084
  | SOME (_, (_, {statement = (_, _, prop), goal, ...})) =>
wenzelm@29385
  1085
      is_schematic prop orelse not (Logic.protect prop aconv Thm.concl_of goal));
wenzelm@29385
  1086
wenzelm@29385
  1087
wenzelm@29385
  1088
(* full proofs *)
wenzelm@28410
  1089
wenzelm@29346
  1090
local
wenzelm@29346
  1091
wenzelm@29385
  1092
fun future_proof done get_context fork_proof state =
wenzelm@28410
  1093
  let
wenzelm@29381
  1094
    val _ = assert_backward state;
wenzelm@28410
  1095
    val (goal_ctxt, (_, goal)) = find_goal state;
wenzelm@32786
  1096
    val {statement as (kind, _, prop), messages, using, goal, before_qed, after_qed} = goal;
wenzelm@47431
  1097
    val goal_tfrees =
wenzelm@47431
  1098
      fold Term.add_tfrees
wenzelm@47431
  1099
        (prop :: map Thm.term_of (Assumption.all_assms_of goal_ctxt)) [];
wenzelm@28410
  1100
wenzelm@29383
  1101
    val _ = is_relevant state andalso error "Cannot fork relevant proof";
wenzelm@29383
  1102
wenzelm@29346
  1103
    val prop' = Logic.protect prop;
wenzelm@29346
  1104
    val statement' = (kind, [[], [prop']], prop');
wenzelm@29346
  1105
    val goal' = Thm.adjust_maxidx_thm (Thm.maxidx_of goal)
wenzelm@29346
  1106
      (Drule.comp_no_flatten (goal, Thm.nprems_of goal) 1 Drule.protectI);
wenzelm@29385
  1107
wenzelm@33386
  1108
    fun after_local' [[th]] = put_thms false (Auto_Bind.thisN, SOME [th]);
wenzelm@42360
  1109
    fun after_global' [[th]] = Proof_Context.put_thms false (Auto_Bind.thisN, SOME [th]);
wenzelm@29385
  1110
    val after_qed' = (after_local', after_global');
wenzelm@42360
  1111
    val this_name = Proof_Context.full_name goal_ctxt (Binding.name Auto_Bind.thisN);
wenzelm@28410
  1112
wenzelm@28973
  1113
    val result_ctxt =
wenzelm@28973
  1114
      state
wenzelm@29385
  1115
      |> map_goal I (K (statement', messages, using, goal', before_qed, after_qed'))
wenzelm@47431
  1116
        (fold (Variable.declare_typ o TFree) goal_tfrees)
wenzelm@29346
  1117
      |> fork_proof;
wenzelm@28973
  1118
wenzelm@29385
  1119
    val future_thm = result_ctxt |> Future.map (fn (_, x) =>
wenzelm@42360
  1120
      Proof_Context.get_fact_single (get_context x) (Facts.named this_name));
wenzelm@32062
  1121
    val finished_goal = Goal.future_result goal_ctxt future_thm prop';
wenzelm@28973
  1122
    val state' =
wenzelm@28973
  1123
      state
wenzelm@47431
  1124
      |> map_goal I (K (statement, messages, using, finished_goal, NONE, after_qed)) I
wenzelm@29385
  1125
      |> done;
wenzelm@28973
  1126
  in (Future.map #1 result_ctxt, state') end;
wenzelm@28410
  1127
wenzelm@29385
  1128
in
wenzelm@29385
  1129
wenzelm@29385
  1130
fun local_future_proof x = future_proof local_done_proof context_of x;
wenzelm@29385
  1131
fun global_future_proof x = future_proof global_done_proof I x;
wenzelm@29385
  1132
wenzelm@17359
  1133
end;
wenzelm@29346
  1134
wenzelm@29385
  1135
wenzelm@29385
  1136
(* terminal proofs *)
wenzelm@29385
  1137
wenzelm@29385
  1138
local
wenzelm@29385
  1139
wenzelm@29385
  1140
fun future_terminal_proof proof1 proof2 meths int state =
wenzelm@38218
  1141
  if int orelse is_relevant state orelse not (Goal.local_future_enabled ())
wenzelm@29385
  1142
  then proof1 meths state
wenzelm@41677
  1143
  else snd (proof2 (fn state' =>
wenzelm@41677
  1144
    Goal.fork_name "Proof.future_terminal_proof" (fn () => ((), proof1 meths state'))) state);
wenzelm@29385
  1145
wenzelm@29385
  1146
in
wenzelm@29385
  1147
wenzelm@29385
  1148
fun local_future_terminal_proof x =
wenzelm@29385
  1149
  future_terminal_proof local_terminal_proof local_future_proof x;
wenzelm@29385
  1150
wenzelm@29385
  1151
fun global_future_terminal_proof x =
wenzelm@29385
  1152
  future_terminal_proof global_terminal_proof global_future_proof x;
wenzelm@29350
  1153
wenzelm@29346
  1154
end;
wenzelm@29346
  1155
wenzelm@29385
  1156
end;
wenzelm@29385
  1157