changeset 253:0446b6c5e7bc

proudct uniquness done
author Shinji KONO <kono@ie.u-ryukyu.ac.jp>
date Thu, 29 Aug 2019 16:08:46 +0900
parents 8a58e2cd1f55
children 2ea2a19f9cd6
files cardinal.agda
diffstat 1 files changed, 6 insertions(+), 2 deletions(-) [+]
line wrap: on
line diff
--- a/cardinal.agda	Thu Aug 29 03:03:04 2019 +0900
+++ b/cardinal.agda	Thu Aug 29 16:08:46 2019 +0900
@@ -125,8 +125,12 @@
 p-iso1 :  { ox oy  : Ordinal } → ZFProduct ∋ < ord→od ox , ord→od oy >  
 p-iso1 {ox} {oy} = pair ox oy
 
-postulate
-    p-iso :  { x  : OD } → (p : ZFProduct ∋ x ) → < ord→od (π1 p) , ord→od (π2 p) > ≡ x
+p-iso :  { x  : OD } → (p : ZFProduct ∋ x ) → < ord→od (π1 p) , ord→od (π2 p) > ≡ x
+p-iso {x} p = ord≡→≡ (lemma2 p) where
+    lemma :  { op : Ordinal } → (q : ord-pair op ) → od→ord < ord→od (pi1 q) , ord→od (pi2 q) > ≡ op
+    lemma (pair ox oy) = refl
+    lemma2 : { x  : OD } → (p : ZFProduct ∋ x ) → od→ord < ord→od (π1 p) , ord→od (π2 p) > ≡ od→ord x
+    lemma2 {x} p = lemma p
 
     
 ∋-p : (A x : OD ) → Dec ( A ∋ x )