| author | berghofe | 
| Mon, 11 Jun 2001 19:21:13 +0200 | |
| changeset 11371 | 1d5d181b7e28 | 
| parent 11326 | 680ebd093cfe | 
| child 11464 | ddea204de5bc | 
| permissions | -rw-r--r-- | 
| 2608 | 1  | 
(* Title: HOL/NatDef.thy  | 
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ID: $Id$  | 
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Author: Tobias Nipkow, Cambridge University Computer Laboratory  | 
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Copyright 1991 University of Cambridge  | 
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Definition of types ind and nat.  | 
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Type nat is defined as a set Nat over type ind.  | 
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*)  | 
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NatDef = Wellfounded_Recursion +  | 
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(** type ind **)  | 
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global  | 
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types  | 
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ind  | 
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arities  | 
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ind :: term  | 
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consts  | 
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Zero_Rep :: ind  | 
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Suc_Rep :: ind => ind  | 
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rules  | 
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(*the axiom of infinity in 2 parts*)  | 
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inj_Suc_Rep "inj(Suc_Rep)"  | 
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Suc_Rep_not_Zero_Rep "Suc_Rep(x) ~= Zero_Rep"  | 
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(** type nat **)  | 
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(* type definition *)  | 
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11326
 
680ebd093cfe
Representing set for type nat is now defined via "inductive".
 
berghofe 
parents: 
10832 
diff
changeset
 | 
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consts  | 
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680ebd093cfe
Representing set for type nat is now defined via "inductive".
 
berghofe 
parents: 
10832 
diff
changeset
 | 
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Nat' :: "ind set"  | 
| 
 
680ebd093cfe
Representing set for type nat is now defined via "inductive".
 
berghofe 
parents: 
10832 
diff
changeset
 | 
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| 
 
680ebd093cfe
Representing set for type nat is now defined via "inductive".
 
berghofe 
parents: 
10832 
diff
changeset
 | 
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inductive Nat'  | 
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680ebd093cfe
Representing set for type nat is now defined via "inductive".
 
berghofe 
parents: 
10832 
diff
changeset
 | 
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intrs  | 
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680ebd093cfe
Representing set for type nat is now defined via "inductive".
 
berghofe 
parents: 
10832 
diff
changeset
 | 
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Zero_RepI "Zero_Rep : Nat'"  | 
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680ebd093cfe
Representing set for type nat is now defined via "inductive".
 
berghofe 
parents: 
10832 
diff
changeset
 | 
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Suc_RepI "i : Nat' ==> Suc_Rep i : Nat'"  | 
| 
 
680ebd093cfe
Representing set for type nat is now defined via "inductive".
 
berghofe 
parents: 
10832 
diff
changeset
 | 
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typedef (Nat)  | 
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11326
 
680ebd093cfe
Representing set for type nat is now defined via "inductive".
 
berghofe 
parents: 
10832 
diff
changeset
 | 
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nat = "Nat'" (Nat'.Zero_RepI)  | 
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instance  | 
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  nat :: {ord, zero}
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(* abstract constants and syntax *)  | 
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consts  | 
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Suc :: nat => nat  | 
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pred_nat :: "(nat * nat) set"  | 
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syntax  | 
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  "1"       :: nat                ("1")
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  "2"       :: nat                ("2")
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translations  | 
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5187
 
55f07169cf5f
Removed nat_case, nat_rec, and natE (now provided by datatype
 
berghofe 
parents: 
3947 
diff
changeset
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"1" == "Suc 0"  | 
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55f07169cf5f
Removed nat_case, nat_rec, and natE (now provided by datatype
 
berghofe 
parents: 
3947 
diff
changeset
 | 
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"2" == "Suc 1"  | 
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local  | 
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defs  | 
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Zero_def "0 == Abs_Nat(Zero_Rep)"  | 
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Suc_def "Suc == (%n. Abs_Nat(Suc_Rep(Rep_Nat(n))))"  | 
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(*nat operations*)  | 
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  pred_nat_def  "pred_nat == {(m,n). n = Suc m}"
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less_def "m<n == (m,n):trancl(pred_nat)"  | 
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le_def "m<=(n::nat) == ~(n<m)"  | 
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end  |