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authorHelmut Grohne <grohne@cs.uni-bonn.de>2014-06-06 09:23:00 +0200
committerHelmut Grohne <grohne@cs.uni-bonn.de>2014-06-06 09:23:00 +0200
commit51dad2ec627203822e1879e3d58ae5331e58d414 (patch)
treec48e1e7abd90f5d9a792f87b07370d9da299a9cd
parent91db824bfa4d66f29066a381e88e6e3125e15576 (diff)
downloadbidiragda-51dad2ec627203822e1879e3d58ae5331e58d414.tar.gz
drop-suc is cong pred
-rw-r--r--Examples.agda7
1 files changed, 2 insertions, 5 deletions
diff --git a/Examples.agda b/Examples.agda
index eca3c90..bda3ae1 100644
--- a/Examples.agda
+++ b/Examples.agda
@@ -1,6 +1,6 @@
module Examples where
-open import Data.Nat using (ℕ ; zero ; suc ; _+_ ; ⌈_/2⌉)
+open import Data.Nat using (ℕ ; zero ; suc ; _+_ ; ⌈_/2⌉ ; pred)
open import Data.Nat.Properties using (cancel-+-left)
import Algebra.Structures
open Algebra.Structures.IsCommutativeSemiring Data.Nat.Properties.isCommutativeSemiring using (+-isCommutativeMonoid)
@@ -34,11 +34,8 @@ double' = assume-get id↪ (≡-to-Π g) f
double'' : Get
double'' = assume-get id↪ (≡-to-Π _) (λ v → v ++ v)
-drop-suc : {n m : ℕ} → suc n ≡ suc m → n ≡ m
-drop-suc refl = refl
-
suc-injection : EqSetoid ℕ ↪ EqSetoid ℕ
-suc-injection = record { to = ≡-to-Π suc; injective = drop-suc }
+suc-injection = record { to = ≡-to-Π suc; injective = cong pred }
tail' : Get
tail' = assume-get suc-injection (≡-to-Π id) tail