added debugging option to find out how good the relevance filter was at identifying relevant facts

--- a/src/HOL/Mirabelle/Tools/mirabelle_sledgehammer.ML	Fri Dec 17 16:55:27 2010 +0100
+++ b/src/HOL/Mirabelle/Tools/mirabelle_sledgehammer.ML	Fri Dec 17 18:23:56 2010 +0100
@@ -577,6 +577,7 @@
 
 fun invoke args =
   let
+    val _ = Sledgehammer_Run.show_facts_in_proofs := true
     val _ = Sledgehammer_Isar.full_types := AList.defined (op =) args full_typesK
   in Mirabelle.register (init, sledgehammer_action args, done) end
 

--- a/src/HOL/Tools/Sledgehammer/sledgehammer_minimize.ML	Fri Dec 17 16:55:27 2010 +0100
+++ b/src/HOL/Tools/Sledgehammer/sledgehammer_minimize.ML	Fri Dec 17 18:23:56 2010 +0100
@@ -10,9 +10,7 @@
   type locality = Sledgehammer_Filter.locality
   type params = Sledgehammer_Provers.params
 
-  val filter_used_facts :
-    (string * locality) list -> ((string * locality) * thm list) list
-    -> ((string * locality) * thm list) list
+  val filter_used_facts : ''a list -> (''a * 'b) list -> (''a * 'b) list
   val minimize_facts :
     params -> bool -> int -> int -> Proof.state
     -> ((string * locality) * thm list) list

--- a/src/HOL/Tools/Sledgehammer/sledgehammer_run.ML	Fri Dec 17 16:55:27 2010 +0100
+++ b/src/HOL/Tools/Sledgehammer/sledgehammer_run.ML	Fri Dec 17 18:23:56 2010 +0100
@@ -13,6 +13,7 @@
   type params = Sledgehammer_Provers.params
 
   (* for experimentation purposes -- do not use in production code *)
+  val show_facts_in_proofs : bool Unsynchronized.ref
   val smt_weights : bool Unsynchronized.ref
   val smt_weight_min_facts : int Unsynchronized.ref
   val smt_min_weight : int Unsynchronized.ref
@@ -47,6 +48,8 @@
    else
      "\n" ^ Syntax.string_of_term ctxt (Thm.term_of (Thm.cprem_of goal i)))
 
+val show_facts_in_proofs = Unsynchronized.ref false
+
 val implicit_minimization_threshold = 50
 
 fun run_prover (params as {debug, blocking, max_relevant, timeout, expect, ...})
@@ -66,22 +69,38 @@
       {state = state, goal = goal, subgoal = subgoal,
        subgoal_count = subgoal_count, facts = take num_facts facts,
        smt_head = smt_head}
+    fun really_go () =
+      prover params (minimize_command name) problem
+      |> (fn {outcome, used_facts, message, ...} =>
+             if is_some outcome then
+               ("none", message)
+             else
+               let
+                 val (used_facts, message) =
+                   if length used_facts >= implicit_minimization_threshold then
+                     minimize_facts params true subgoal subgoal_count state
+                         (filter_used_facts used_facts
+                              (map (apsnd single o untranslated_fact) facts))
+                     |>> Option.map (map fst)
+                   else
+                     (SOME used_facts, message)
+                 val _ =
+                   case (debug orelse !show_facts_in_proofs, used_facts) of
+                     (true, SOME (used_facts as _ :: _)) =>
+                     facts ~~ (0 upto length facts - 1)
+                     |> map (fn (fact, j) =>
+                                fact |> untranslated_fact |> apsnd (K j))
+                     |> filter_used_facts used_facts
+                     |> map (fn ((name, _), j) => name ^ "@" ^ string_of_int j)
+                     |> commas
+                     |> enclose ("Fact" ^ plural_s num_facts ^ " in " ^
+                                 quote name ^ " proof (of " ^
+                                 string_of_int num_facts ^ "): ") "."
+                     |> Output.urgent_message
+                   | _ => ()
+               in ("some", message) end)
     fun go () =
       let
-        fun really_go () =
-          prover params (minimize_command name) problem
-          |> (fn {outcome, used_facts, message, ...} =>
-                 if is_some outcome then
-                   ("none", message)
-                 else
-                   ("some",
-                    if length used_facts >= implicit_minimization_threshold then
-                      minimize_facts params true subgoal subgoal_count state
-                          (filter_used_facts used_facts
-                               (map (apsnd single o untranslated_fact) facts))
-                      |> snd
-                    else
-                      message))
         val (outcome_code, message) =
           if debug then
             really_go ()