changeset 614:e6be03d94284

Representational Functor preserve limit done
author Shinji KONO <kono@ie.u-ryukyu.ac.jp>
date Tue, 13 Jun 2017 22:53:44 +0900
parents afddfebea797
children a45c32ceca97
files freyd2.agda
diffstat 1 files changed, 15 insertions(+), 1 deletions(-) [+]
line wrap: on
line diff
--- a/freyd2.agda	Tue Jun 13 22:36:54 2017 +0900
+++ b/freyd2.agda	Tue Jun 13 22:53:44 2017 +0900
@@ -120,7 +120,7 @@
 UpreserveLimit0 {c₁} {c₂} {ℓ} A I b Γ lim = record {
          limit = λ a t → ψ a t
        ; t0f=t = λ {a t i} → t0f=t0 a t i
-       ; limit-uniqueness = λ {b} {t} {f} t0f=t → {!!}
+       ; limit-uniqueness = λ {b} {t} {f} t0f=t → limit-uniqueness0 {b} {t} {f} t0f=t 
     } where 
       hat0 :  NTrans I Sets (K Sets I (FObj (HomA A b) (a0 lim))) (HomA A b ○ Γ)
       hat0 = LimitNat A I Sets Γ (a0 lim) (t0 lim) (HomA A b)
@@ -163,6 +163,20 @@
              ≈⟨⟩
                  TMap t i x
              ∎  ))
+      limit-uniqueness0 :  {a : Obj Sets} {t : NTrans I Sets (K Sets I a) (HomA A b ○ Γ)} {f : Hom Sets a (FObj (HomA A b) (a0 lim))} →
+        ({i : Obj I} → Sets [ Sets [ TMap (LimitNat A I Sets Γ (a0 lim) (t0 lim) (HomA A b)) i o f ] ≈ TMap t i ]) →
+        Sets [ ψ a t ≈ f ]
+      limit-uniqueness0 {a} {t} {f} t0f=t = let open ≈-Reasoning A in extensionality A ( λ x →  ≈-≡ A ( begin 
+                  ψ a t x
+             ≈⟨⟩
+                 FMap (HomA A b) (limit (isLimit lim) b (ta a x t )) (id1 A b )
+             ≈⟨⟩
+                 limit (isLimit lim) b (ta a x t ) o id1 A b 
+             ≈⟨ idR ⟩
+                 limit (isLimit lim) b (ta a x t ) 
+             ≈⟨ limit-uniqueness (isLimit lim) ( λ {i} → ≡-≈ ( cong ( λ g → g x )( t0f=t {i} ))) ⟩
+                  f x
+             ∎  ))
 
 
 UpreserveLimit : {c₁ c₂ ℓ : Level} (A : Category c₁ c₂ ℓ) (I : Category c₁ c₂ ℓ)