diff --git a/library/init/algebra/order.lean b/library/init/algebra/order.lean index 26c7b72056..076c57113c 100644 --- a/library/init/algebra/order.lean +++ b/library/init/algebra/order.lean @@ -42,21 +42,30 @@ class linear_strong_order_pair (α : Type u) extends strong_order_pair α, linea class decidable_linear_order (α : Type u) extends linear_strong_order_pair α := (decidable_lt : decidable_rel lt) +attribute [refl] lemma le_refl [weak_order α] : ∀ a : α, a ≤ a := weak_order.le_refl +def le.refl := @le_refl + +attribute [trans] lemma le_trans [weak_order α] : ∀ {a b c : α}, a ≤ b → b ≤ c → a ≤ c := weak_order.le_trans +def le.trans := @le_trans + lemma le_antisymm [weak_order α] : ∀ {a b : α}, a ≤ b → b ≤ a → a = b := weak_order.le_antisymm lemma le_of_eq [weak_order α] {a b : α} : a = b → a ≤ b := λ h, h ▸ le_refl a +attribute [trans] lemma ge_trans [weak_order α] : ∀ {a b c : α}, a ≥ b → b ≥ c → a ≥ c := λ a b c h₁ h₂, le_trans h₂ h₁ +def ge.trans := @ge_trans + lemma le_total [linear_weak_order α] : ∀ a b : α, a ≤ b ∨ b ≤ a := linear_weak_order.le_total @@ -69,12 +78,18 @@ strict_order.lt_irrefl lemma gt_irrefl [strict_order α] : ∀ a : α, ¬ a > a := lt_irrefl +attribute [trans] lemma lt_trans [strict_order α] : ∀ {a b c : α}, a < b → b < c → a < c := strict_order.lt_trans +def lt.trans := @lt_trans + +attribute [trans] lemma gt_trans [strict_order α] : ∀ {a b c : α}, a > b → b > c → a > c := λ a b c h₁ h₂, lt_trans h₂ h₁ +def gt.trans := @gt_trans + lemma ne_of_lt [strict_order α] {a b : α} (h : a < b) : a ≠ b := λ he, absurd h (he ▸ lt_irrefl a) @@ -90,15 +105,19 @@ lt_asymm h lemma le_of_lt [order_pair α] : ∀ {a b : α}, a < b → a ≤ b := order_pair.le_of_lt +attribute [trans] lemma lt_of_lt_of_le [order_pair α] : ∀ {a b c : α}, a < b → b ≤ c → a < c := order_pair.lt_of_lt_of_le +attribute [trans] lemma lt_of_le_of_lt [order_pair α] : ∀ {a b c : α}, a ≤ b → b < c → a < c := order_pair.lt_of_le_of_lt +attribute [trans] lemma gt_of_gt_of_ge [order_pair α] {a b c : α} (h₁ : a > b) (h₂ : b ≥ c) : a > c := lt_of_le_of_lt h₂ h₁ +attribute [trans] lemma gt_of_ge_of_gt [order_pair α] {a b c : α} (h₁ : a ≥ b) (h₂ : b > c) : a > c := lt_of_lt_of_le h₂ h₁