adding hotel keycard example for prolog generation

--- a/src/HOL/IsaMakefile	Wed Aug 25 16:59:48 2010 +0200
+++ b/src/HOL/IsaMakefile	Wed Aug 25 16:59:49 2010 +0200
@@ -1321,7 +1321,8 @@
   Predicate_Compile_Examples/ROOT.ML					\
   Predicate_Compile_Examples/Predicate_Compile_Examples.thy		\
   Predicate_Compile_Examples/Predicate_Compile_Quickcheck_Examples.thy  \
-  Predicate_Compile_Examples/Code_Prolog_Examples.thy
+  Predicate_Compile_Examples/Code_Prolog_Examples.thy 			\
+  Predicate_Compile_Examples/Hotel_Example.thy
 	@$(ISABELLE_TOOL) usedir $(OUT)/HOL Predicate_Compile_Examples
 
 

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/HOL/Predicate_Compile_Examples/Hotel_Example.thy	Wed Aug 25 16:59:49 2010 +0200
@@ -0,0 +1,93 @@
+theory Hotel_Example
+imports Predicate_Compile_Alternative_Defs Code_Prolog
+begin
+
+datatype guest = Guest0 | Guest1
+datatype key = Key0 | Key1 | Key2 | Key3
+datatype room = Room0
+
+types card = "key * key"
+
+datatype event =
+   Check_in guest room card | Enter guest room card | Exit guest room
+
+definition initk :: "room \<Rightarrow> key"
+  where "initk = (%r. Key0)"
+
+declare initk_def[code_pred_def, code]
+
+primrec owns :: "event list \<Rightarrow> room \<Rightarrow> guest option"
+where
+  "owns [] r = None"
+| "owns (e#s) r = (case e of
+    Check_in g r' c \<Rightarrow> if r' = r then Some g else owns s r |
+    Enter g r' c \<Rightarrow> owns s r |
+    Exit g r' \<Rightarrow> owns s r)"
+
+primrec currk :: "event list \<Rightarrow> room \<Rightarrow> key"
+where
+  "currk [] r = initk r"
+| "currk (e#s) r = (let k = currk s r in
+    case e of Check_in g r' (k1, k2) \<Rightarrow> if r' = r then k2 else k
+            | Enter g r' c \<Rightarrow> k
+            | Exit g r \<Rightarrow> k)"
+
+primrec issued :: "event list \<Rightarrow> key set"
+where
+  "issued [] = range initk"
+| "issued (e#s) = issued s \<union>
+  (case e of Check_in g r (k1, k2) \<Rightarrow> {k2} | Enter g r c \<Rightarrow> {} | Exit g r \<Rightarrow> {})"
+
+primrec cards :: "event list \<Rightarrow> guest \<Rightarrow> card set"
+where
+  "cards [] g = {}"
+| "cards (e#s) g = (let C = cards s g in
+                    case e of Check_in g' r c \<Rightarrow> if g' = g then insert c C
+                                                else C
+                            | Enter g r c \<Rightarrow> C
+                            | Exit g r \<Rightarrow> C)"
+
+primrec roomk :: "event list \<Rightarrow> room \<Rightarrow> key"
+where
+  "roomk [] r = initk r"
+| "roomk (e#s) r = (let k = roomk s r in
+    case e of Check_in g r' c \<Rightarrow> k
+            | Enter g r' (x,y) \<Rightarrow> if r' = r (*& x = k*) then y else k
+            | Exit g r \<Rightarrow> k)"
+
+primrec isin :: "event list \<Rightarrow> room \<Rightarrow> guest set"
+where
+  "isin [] r = {}"
+| "isin (e#s) r = (let G = isin s r in
+                 case e of Check_in g r c \<Rightarrow> G
+                 | Enter g r' c \<Rightarrow> if r' = r then {g} \<union> G else G
+                 | Exit g r' \<Rightarrow> if r'=r then G - {g} else G)"
+
+primrec hotel :: "event list \<Rightarrow> bool"
+where
+  "hotel []  = True"
+| "hotel (e # s) = (hotel s & (case e of
+  Check_in g r (k,k') \<Rightarrow> k = currk s r \<and> k' \<notin> issued s |
+  Enter g r (k,k') \<Rightarrow> (k,k') : cards s g & (roomk s r : {k, k'}) |
+  Exit g r \<Rightarrow> False))"
+
+lemma issued_nil: "issued [] = {Key0}"
+by (auto simp add: initk_def)
+
+lemmas issued_simps[code, code_pred_def] = issued_nil issued.simps(2)
+
+declare Let_def[code_pred_inline]
+
+lemma [code_pred_inline]: "insert == (%y A x. y = x | A x)"
+by (auto simp add: insert_iff[unfolded mem_def] expand_fun_eq intro!: eq_reflection)
+
+lemma [code_pred_inline]: "(op -) == (%A B x. A x \<and> \<not> B x)"
+by (auto simp add: Diff_iff[unfolded mem_def] expand_fun_eq intro!: eq_reflection)
+
+code_pred [new_random_dseq inductify, skip_proof] hotel .
+
+ML {* Code_Prolog.options := {ensure_groundness = true} *}
+
+values 10 "{s. hotel s}"
+
+end
\ No newline at end of file

--- a/src/HOL/Predicate_Compile_Examples/ROOT.ML	Wed Aug 25 16:59:48 2010 +0200
+++ b/src/HOL/Predicate_Compile_Examples/ROOT.ML	Wed Aug 25 16:59:49 2010 +0200
@@ -1,2 +1,2 @@
 use_thys ["Predicate_Compile_Examples", "Predicate_Compile_Quickcheck_Examples", "Specialisation_Examples"];
-if getenv "PROLOG_HOME" = "" then () else use_thys ["Code_Prolog_Examples"];
+if getenv "PROLOG_HOME" = "" then () else use_thys ["Code_Prolog_Examples", "Hotel_Example"];