| author | clasohm | 
| Sat, 09 Dec 1995 13:36:11 +0100 | |
| changeset 1401 | 0c439768f45c | 
| parent 837 | 778f01546669 | 
| child 1478 | 2b8c2a7547ab | 
| permissions | -rw-r--r-- | 
| 0 | 1  | 
(* Title: ZF/bool.thy  | 
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ID: $Id$  | 
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Author: Lawrence C Paulson, Cambridge University Computer Laboratory  | 
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Copyright 1992 University of Cambridge  | 
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Booleans in Zermelo-Fraenkel Set Theory  | 
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2 is equal to bool, but serves a different purpose  | 
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*)  | 
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Bool = ZF + "simpdata" +  | 
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consts  | 
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    "1"		:: i     	   ("1")
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    "2"         :: i             ("2")
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bool :: i  | 
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cond :: [i,i,i]=>i  | 
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not :: i=>i  | 
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"and" :: [i,i]=>i (infixl 70)  | 
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or :: [i,i]=>i (infixl 65)  | 
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xor :: [i,i]=>i (infixl 65)  | 
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14
 
1c0926788772
ex/{bin.ML,comb.ML,prop.ML}: replaced NewSext by Syntax.simple_sext
 
lcp 
parents: 
0 
diff
changeset
 | 
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translations  | 
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1c0926788772
ex/{bin.ML,comb.ML,prop.ML}: replaced NewSext by Syntax.simple_sext
 
lcp 
parents: 
0 
diff
changeset
 | 
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"1" == "succ(0)"  | 
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"2" == "succ(1)"  | 
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14
 
1c0926788772
ex/{bin.ML,comb.ML,prop.ML}: replaced NewSext by Syntax.simple_sext
 
lcp 
parents: 
0 
diff
changeset
 | 
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defs  | 
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    bool_def	"bool == {0,1}"
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cond_def "cond(b,c,d) == if(b=1,c,d)"  | 
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not_def "not(b) == cond(b,0,1)"  | 
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and_def "a and b == cond(a,b,0)"  | 
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or_def "a or b == cond(a,1,b)"  | 
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xor_def "a xor b == cond(a,not(b),b)"  | 
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end  |