Context data for QE in DLO (Langford's algorithm)

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/HOL/Tools/Qelim/langford_data.ML	Sun Jul 22 17:53:55 2007 +0200
@@ -0,0 +1,110 @@
+signature LANGFORD_DATA =
+sig
+  type entry
+  val get: Proof.context -> simpset * (thm * entry) list
+  val add: entry -> attribute 
+  val del: attribute
+  val setup: theory -> theory
+  val match: Proof.context -> cterm -> entry option
+end;
+
+structure Langford_Data: LANGFORD_DATA = 
+struct
+
+(* data *)
+type entry = {qe_bnds: thm, qe_nolb : thm , qe_noub: thm, 
+              gs : thm list, gst : thm, atoms: cterm list};
+val eq_key = Thm.eq_thm;
+fun eq_data arg = eq_fst eq_key arg;
+
+structure Data = GenericDataFun
+( type T = simpset * (thm * entry) list;
+  val empty = (HOL_basic_ss, []);
+  val extend = I;
+  fun merge _ ((ss1,es1), (ss2,es2)) = 
+       (merge_ss (ss1,ss2), AList.merge eq_key (K true) (es1,es2));;
+);
+
+val get = Data.get o Context.Proof;
+
+fun del_data key = apsnd (remove eq_data (key, []));
+
+val del = Thm.declaration_attribute (Data.map o del_data);
+
+fun add entry = 
+    Thm.declaration_attribute (fn key => fn context => context |> Data.map 
+      (del_data key #> apsnd (cons (key, entry))));
+
+val add_simp = Thm.declaration_attribute (fn th => fn context => 
+  context |> Data.map (fn (ss,ts') => (ss addsimps [th], ts'))) 
+
+val del_simp = Thm.declaration_attribute (fn th => fn context => 
+  context |> Data.map (fn (ss,ts') => (ss delsimps [th], ts'))) 
+
+fun match ctxt tm =
+  let
+    fun match_inst
+        {qe_bnds, qe_nolb, qe_noub, gs, gst, atoms} pat =
+       let
+        fun h instT =
+          let
+            val substT = Thm.instantiate (instT, []);
+            val substT_cterm = Drule.cterm_rule substT;
+
+            val qe_bnds' = substT qe_bnds
+            val qe_nolb' = substT qe_nolb
+            val qe_noub' = substT qe_noub
+            val gs' = map substT gs
+            val gst' = substT gst
+            val atoms' = map substT_cterm atoms
+            val result = {qe_bnds = qe_bnds', qe_nolb = qe_nolb', 
+                          qe_noub = qe_noub', gs = gs', gst = gst', 
+                          atoms = atoms'}
+          in SOME result end
+      in (case try Thm.match (pat, tm) of
+           NONE => NONE
+         | SOME (instT, _) => h instT)
+      end;
+
+    fun match_struct (_,
+        entry as ({atoms = atoms, ...}): entry) =
+      get_first (match_inst entry) atoms;
+  in get_first match_struct (snd (get ctxt)) end;
+
+(* concrete syntax *)
+
+local
+val qeN = "qe";
+val gatherN = "gather";
+val atomsN = "atoms"
+fun keyword k = Scan.lift (Args.$$$ k -- Args.colon) >> K ();
+val any_keyword =
+  keyword qeN || keyword gatherN || keyword atomsN;
+
+val thms = Scan.repeat (Scan.unless any_keyword Attrib.multi_thm) >> flat;
+val terms = thms >> map Drule.dest_term;
+in
+
+fun att_syntax src = src |> Attrib.syntax
+    ((keyword qeN |-- thms)
+     -- (keyword gatherN |-- thms)
+     -- (keyword atomsN |-- terms) >> 
+     (fn ((qes,gs), atoms) => 
+     if length qes = 3 andalso length gs > 1 then
+       let 
+         val [q1,q2,q3] = qes
+         val gst::gss = gs
+         val entry = {qe_bnds = q1, qe_nolb = q2,
+                      qe_noub = q3, gs = gss, gst = gst, atoms = atoms}
+       in add entry end
+     else error "Need 3 theorems for qe and at least one for gs"))
+end;
+
+(* theory setup *)
+
+val setup =
+  Attrib.add_attributes 
+[("langford", att_syntax, "Langford data"),
+ ("langfordsimp", Attrib.add_del_args add_simp del_simp, "Langford simpset")];
+
+end;