src/Pure/thm_deps.ML

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/Pure/thm_deps.ML	Thu Oct 17 20:28:31 2019 +0200
@@ -0,0 +1,135 @@
+(*  Title:      Pure/thm_deps.ML
+    Author:     Stefan Berghofer, TU Muenchen
+    Author:     Makarius
+
+Dependencies of theorems wrt. internal derivation.
+*)
+
+signature THM_DEPS =
+sig
+  val all_oracles: thm list -> Proofterm.oracle list
+  val has_skip_proof: thm list -> bool
+  val pretty_thm_oracles: Proof.context -> thm list -> Pretty.T
+  val thm_deps: theory -> thm list -> (Proofterm.thm_id * Thm_Name.T) list
+  val pretty_thm_deps: theory -> thm list -> Pretty.T
+  val unused_thms_cmd: theory list * theory list -> (string * thm) list
+end;
+
+structure Thm_Deps: THM_DEPS =
+struct
+
+(* oracles *)
+
+fun all_oracles thms =
+  let
+    fun collect (PBody {oracles, thms, ...}) =
+      (if null oracles then I else apfst (cons oracles)) #>
+      (tap Proofterm.join_thms thms |> fold (fn (i, thm_node) => fn (res, seen) =>
+        if Inttab.defined seen i then (res, seen)
+        else
+          let val body = Future.join (Proofterm.thm_node_body thm_node)
+          in collect body (res, Inttab.update (i, ()) seen) end));
+    val bodies = map Thm.proof_body_of thms;
+  in fold collect bodies ([], Inttab.empty) |> #1 |> Proofterm.unions_oracles end;
+
+fun has_skip_proof thms =
+  all_oracles thms |> exists (fn (name, _) => name = \<^oracle_name>\<open>skip_proof\<close>);
+
+fun pretty_thm_oracles ctxt thms =
+  let
+    val thy = Proof_Context.theory_of ctxt;
+    fun prt_oracle (name, NONE) = [Thm.pretty_oracle ctxt name]
+      | prt_oracle (name, SOME prop) =
+          [Thm.pretty_oracle ctxt name, Pretty.str ":", Pretty.brk 1,
+            Syntax.pretty_term_global thy prop];
+  in Pretty.big_list "oracles:" (map (Pretty.item o prt_oracle) (all_oracles thms)) end;
+
+
+(* thm_deps *)
+
+fun thm_deps thy =
+  let
+    val lookup = Global_Theory.lookup_thm_id thy;
+    fun deps (i, thm_node) res =
+      if Inttab.defined res i then res
+      else
+        let val thm_id = Proofterm.thm_id (i, thm_node) in
+          (case lookup thm_id of
+            SOME thm_name =>
+              Inttab.update (i, SOME (thm_id, thm_name)) res
+          | NONE =>
+              Inttab.update (i, NONE) res
+              |> fold deps (Proofterm.thm_node_thms thm_node))
+        end;
+  in
+    fn thms =>
+      (fold (fold deps o Thm.thm_deps o Thm.transfer thy) thms Inttab.empty, [])
+      |-> Inttab.fold_rev (fn (_, SOME entry) => cons entry | _ => I)
+  end;
+
+fun pretty_thm_deps thy thms =
+  let
+    val ctxt = Proof_Context.init_global thy;
+    val items =
+      map #2 (thm_deps thy thms)
+      |> map (fn (name, i) => (Proof_Context.markup_extern_fact ctxt name, i))
+      |> sort_by (#2 o #1)
+      |> map (fn ((marks, xname), i) =>
+          Pretty.item [Pretty.marks_str (marks, Thm_Name.print (xname, i))]);
+  in Pretty.big_list ("dependencies: " ^ string_of_int (length items)) items end;
+
+
+(* unused_thms_cmd *)
+
+fun unused_thms_cmd (base_thys, thys) =
+  let
+    fun add_fact transfer space (name, ths) =
+      if exists (fn thy => Global_Theory.defined_fact thy name) base_thys then I
+      else
+        let val {concealed, group, ...} = Name_Space.the_entry space name in
+          fold_rev (fn th =>
+            (case Thm.derivation_name th of
+              "" => I
+            | a => cons (a, (transfer th, concealed, group)))) ths
+        end;
+    fun add_facts thy =
+      let
+        val transfer = Global_Theory.transfer_theories thy;
+        val facts = Global_Theory.facts_of thy;
+      in Facts.fold_static (add_fact transfer (Facts.space_of facts)) facts end;
+
+    val new_thms =
+      fold add_facts thys []
+      |> sort_distinct (string_ord o apply2 #1);
+
+    val used =
+      Proofterm.fold_body_thms
+        (fn {name = a, ...} => a <> "" ? Symtab.update (a, ()))
+        (map Proofterm.strip_thm_body (Thm.proof_bodies_of (map (#1 o #2) new_thms)))
+        Symtab.empty;
+
+    fun is_unused a = not (Symtab.defined used a);
+
+    (*groups containing at least one used theorem*)
+    val used_groups = fold (fn (a, (_, _, group)) =>
+      if is_unused a then I
+      else
+        (case group of
+          NONE => I
+        | SOME grp => Inttab.update (grp, ()))) new_thms Inttab.empty;
+
+    val (thms', _) = fold (fn (a, (th, concealed, group)) => fn q as (thms, seen_groups) =>
+      if not concealed andalso
+        (* FIXME replace by robust treatment of thm groups *)
+        Thm.legacy_get_kind th = Thm.theoremK andalso is_unused a
+      then
+        (case group of
+           NONE => ((a, th) :: thms, seen_groups)
+         | SOME grp =>
+             if Inttab.defined used_groups grp orelse
+               Inttab.defined seen_groups grp then q
+             else ((a, th) :: thms, Inttab.update (grp, ()) seen_groups))
+      else q) new_thms ([], Inttab.empty);
+  in rev thms' end;
+
+end;