--- a/src/HOL/Induct/Mutil.thy Sat Mar 04 11:52:42 2000 +0100
+++ b/src/HOL/Induct/Mutil.thy Sat Mar 04 12:02:41 2000 +0100
@@ -8,25 +8,25 @@
Popularized as the Mutilated Checkerboard Problem by J McCarthy
*)
-Mutil = Finite +
-consts
- domino :: "(nat*nat)set set"
- tiling :: "'a set set => 'a set set"
- below :: "nat => nat set"
- evnodd :: "[(nat*nat)set, nat] => (nat*nat)set"
+Mutil = Main +
+consts domino :: "(nat*nat)set set"
inductive domino
intrs
horiz "{(i, j), (i, Suc j)} : domino"
vertl "{(i, j), (Suc i, j)} : domino"
+consts tiling :: "'a set set => 'a set set"
inductive "tiling A"
intrs
empty "{} : tiling A"
Un "[| a: A; t: tiling A; a <= -t |] ==> a Un t : tiling A"
-defs
- below_def "below n == {i. i<n}"
- evnodd_def "evnodd A b == A Int {(i,j). (i+j) mod 2 = b}"
+constdefs
+ below :: "nat => nat set"
+ "below n == {i. i<n}"
+
+ evnodd :: "[(nat*nat)set, nat] => (nat*nat)set"
+ "evnodd A b == A Int {(i,j). (i+j) mod 2 = b}"
end