diff --git a/Lattice.agda b/Lattice.agda index 132ad0f..af572aa 100644 --- a/Lattice.agda +++ b/Lattice.agda @@ -24,6 +24,12 @@ record IsSemilattice {a} (A : Set a) (_≈_ : A → A → Set a) (_⊔_ : A → A → A) : Set a where + _≼_ : A → A → Set a + a ≼ b = Σ A (λ c → (a ⊔ c) ≈ b) + + _≺_ : A → A → Set a + a ≺ b = (a ≼ b) × (¬ a ≈ b) + field ≈-equiv : IsEquivalence A _≈_ @@ -46,7 +52,7 @@ record IsLattice {a} (A : Set a) absorb-⊓-⊔ : (x y : A) → (x ⊓ (x ⊔ y)) ≈ x open IsSemilattice joinSemilattice public - open IsSemilattice meetSemilattice public hiding (≈-equiv; ≈-refl; ≈-sym; ≈-trans) renaming + open IsSemilattice meetSemilattice public using () renaming ( ⊔-assoc to ⊓-assoc ; ⊔-comm to ⊓-comm ; ⊔-idemp to ⊓-idemp @@ -58,15 +64,9 @@ record IsFiniteHeightLattice {a} (A : Set a) (_⊔_ : A → A → A) (_⊓_ : A → A → A) : Set (lsuc a) where - _≼_ : A → A → Set a - a ≼ b = Σ A (λ c → (a ⊔ c) ≈ b) - - _≺_ : A → A → Set a - a ≺ b = (a ≼ b) × (¬ a ≈ b) - field isLattice : IsLattice A _≈_ _⊔_ _⊓_ - fixedHeight : Height _≺_ h + fixedHeight : Height (IsLattice._≺_ isLattice) h open IsLattice isLattice public