src/HOL/Library/Quickcheck.thy
changeset 31190 80b7adb23866
parent 31177 c39994cb152a
parent 31189 7d43c7d3a15c
child 31191 7733125bac3c
--- a/src/HOL/Library/Quickcheck.thy	Mon May 18 09:48:06 2009 +0200
+++ /dev/null	Thu Jan 01 00:00:00 1970 +0000
@@ -1,148 +0,0 @@
-(* Author: Florian Haftmann, TU Muenchen *)
-
-header {* A simple counterexample generator *}
-
-theory Quickcheck
-imports Random Code_Eval Map
-begin
-
-subsection {* The @{text random} class *}
-
-class random = typerep +
-  fixes random :: "index \<Rightarrow> seed \<Rightarrow> ('a \<times> (unit \<Rightarrow> term)) \<times> seed"
-
-text {* Type @{typ "'a itself"} *}
-
-instantiation itself :: ("{type, typerep}") random
-begin
-
-definition
-  "random _ = Pair (TYPE('a), \<lambda>u. Code_Eval.Const (STR ''TYPE'') TYPEREP('a))"
-
-instance ..
-
-end
-
-
-subsection {* Quickcheck generator *}
-
-ML {*
-structure StateMonad =
-struct
-
-fun liftT T sT = sT --> HOLogic.mk_prodT (T, sT);
-fun liftT' sT = sT --> sT;
-
-fun return T sT x = Const (@{const_name Pair}, T --> liftT T sT) $ x;
-
-fun scomp T1 T2 sT f g = Const (@{const_name scomp},
-  liftT T1 sT --> (T1 --> liftT T2 sT) --> liftT T2 sT) $ f $ g;
-
-end;
-
-structure Quickcheck =
-struct
-
-open Quickcheck;
-
-val eval_ref : (unit -> int -> int * int -> term list option * (int * int)) option ref = ref NONE;
-
-val target = "Quickcheck";
-
-fun mk_generator_expr thy prop tys =
-  let
-    val bound_max = length tys - 1;
-    val bounds = map_index (fn (i, ty) =>
-      (2 * (bound_max - i) + 1, 2 * (bound_max - i), 2 * i, ty)) tys;
-    val result = list_comb (prop, map (fn (i, _, _, _) => Bound i) bounds);
-    val terms = HOLogic.mk_list @{typ term} (map (fn (_, i, _, _) => Bound i $ @{term "()"}) bounds);
-    val check = @{term "If \<Colon> bool \<Rightarrow> term list option \<Rightarrow> term list option \<Rightarrow> term list option"}
-      $ result $ @{term "None \<Colon> term list option"} $ (@{term "Some \<Colon> term list \<Rightarrow> term list option "} $ terms);
-    val return = @{term "Pair \<Colon> term list option \<Rightarrow> seed \<Rightarrow> term list option \<times> seed"};
-    fun mk_termtyp ty = HOLogic.mk_prodT (ty, @{typ "unit \<Rightarrow> term"});
-    fun mk_split ty = Sign.mk_const thy
-      (@{const_name split}, [ty, @{typ "unit \<Rightarrow> term"}, StateMonad.liftT @{typ "term list option"} @{typ seed}]);
-    fun mk_scomp_split ty t t' =
-      StateMonad.scomp (mk_termtyp ty) @{typ "term list option"} @{typ seed} t (*FIXME*)
-        (mk_split ty $ Abs ("", ty, Abs ("", @{typ "unit \<Rightarrow> term"}, t')));
-    fun mk_bindclause (_, _, i, ty) = mk_scomp_split ty
-      (Sign.mk_const thy (@{const_name random}, [ty]) $ Bound i)
-    val t = fold_rev mk_bindclause bounds (return $ check);
-  in Abs ("n", @{typ index}, t) end;
-
-fun compile_generator_expr thy t =
-  let
-    val tys = (map snd o fst o strip_abs) t;
-    val t' = mk_generator_expr thy t tys;
-    val f = Code_ML.eval (SOME target) ("Quickcheck.eval_ref", eval_ref)
-      (fn proc => fn g => fn s => g (s + 1) #>> (Option.map o map) proc) thy t' [];
-  in f #> Random_Engine.run end;
-
-end
-*}
-
-setup {*
-  Code_Target.extend_target (Quickcheck.target, (Code_ML.target_Eval, K I))
-  #> Quickcheck.add_generator ("code", Quickcheck.compile_generator_expr o ProofContext.theory_of)
-*}
-
-
-subsection {* Type @{typ "'a \<Rightarrow> 'b"} *}
-
-ML {*
-structure Random_Engine =
-struct
-
-open Random_Engine;
-
-fun random_fun (T1 : typ) (T2 : typ) (eq : 'a -> 'a -> bool) (term_of : 'a -> term)
-    (random : Random_Engine.seed -> ('b * (unit -> term)) * Random_Engine.seed)
-    (random_split : Random_Engine.seed -> Random_Engine.seed * Random_Engine.seed)
-    (seed : Random_Engine.seed) =
-  let
-    val (seed', seed'') = random_split seed;
-    val state = ref (seed', [], Const (@{const_name undefined}, T1 --> T2));
-    val fun_upd = Const (@{const_name fun_upd},
-      (T1 --> T2) --> T1 --> T2 --> T1 --> T2);
-    fun random_fun' x =
-      let
-        val (seed, fun_map, f_t) = ! state;
-      in case AList.lookup (uncurry eq) fun_map x
-       of SOME y => y
-        | NONE => let
-              val t1 = term_of x;
-              val ((y, t2), seed') = random seed;
-              val fun_map' = (x, y) :: fun_map;
-              val f_t' = fun_upd $ f_t $ t1 $ t2 ();
-              val _ = state := (seed', fun_map', f_t');
-            in y end
-      end;
-    fun term_fun' () = #3 (! state);
-  in ((random_fun', term_fun'), seed'') end;
-
-end
-*}
-
-axiomatization
-  random_fun_aux :: "typerep \<Rightarrow> typerep \<Rightarrow> ('a \<Rightarrow> 'a \<Rightarrow> bool) \<Rightarrow> ('a \<Rightarrow> term)
-    \<Rightarrow> (seed \<Rightarrow> ('b \<times> (unit \<Rightarrow> term)) \<times> seed) \<Rightarrow> (seed \<Rightarrow> seed \<times> seed)
-    \<Rightarrow> seed \<Rightarrow> (('a \<Rightarrow> 'b) \<times> (unit \<Rightarrow> term)) \<times> seed"
-
-code_const random_fun_aux (Quickcheck "Random'_Engine.random'_fun")
-  -- {* With enough criminal energy this can be abused to derive @{prop False};
-  for this reason we use a distinguished target @{text Quickcheck}
-  not spoiling the regular trusted code generation *}
-
-instantiation "fun" :: ("{eq, term_of}", "{type, random}") random
-begin
-
-definition random_fun :: "index \<Rightarrow> seed \<Rightarrow> (('a \<Rightarrow> 'b) \<times> (unit \<Rightarrow> term)) \<times> seed" where
-  "random n = random_fun_aux TYPEREP('a) TYPEREP('b) (op =) Code_Eval.term_of (random n) split_seed"
-
-instance ..
-
-end
-
-code_reserved Quickcheck Random_Engine
-
-end