mathlib documentation

order.​category.​Preorder

order.​category.​Preorder

Category of preorders

def Preorder  :
Type (u_1+1)

The category of preorders.

Equations
structure preorder_hom (α : Type u_1) (β : Type u_2) [preorder α] [preorder β] :
Type (max u_1 u_2)

Bundled monotone (aka, increasing) function

@[instance]
def preorder_hom.​has_coe_to_fun {α : Type u_1} {β : Type u_2} [preorder α] [preorder β] :

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@[ext]
theorem preorder_hom.​ext {α : Type u_1} {β : Type u_2} [preorder α] [preorder β] (f g : preorder_hom α β) :
(∀ (a : α), ⇑f a = ⇑g a) → f = g

theorem preorder_hom.​coe_inj {α : Type u_1} {β : Type u_2} [preorder α] [preorder β] (f g : preorder_hom α β) :
⇑f = ⇑g → f = g

@[simp]
theorem preorder_hom.​id_to_fun {α : Type u_1} [preorder α] (a : α) :

def preorder_hom.​id {α : Type u_1} [preorder α] :

The identity function as bundled monotone function.

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@[instance]
def preorder_hom.​inhabited {α : Type u_1} [preorder α] :

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@[simp]
theorem preorder_hom.​comp_to_fun {α : Type u_1} {β : Type u_2} {γ : Type u_3} [preorder α] [preorder β] [preorder γ] (g : preorder_hom β γ) (f : preorder_hom α β) (a : α) :
⇑(g.comp f) a = (⇑g ∘ ⇑f) a

def preorder_hom.​comp {α : Type u_1} {β : Type u_2} {γ : Type u_3} [preorder α] [preorder β] [preorder γ] :
preorder_hom β γ → preorder_hom α β → preorder_hom α γ

The composition of two bundled monotone functions.

Equations
@[simp]
theorem preorder_hom.​comp_id {α : Type u_1} {β : Type u_2} [preorder α] [preorder β] (f : preorder_hom α β) :

@[simp]
theorem preorder_hom.​id_comp {α : Type u_1} {β : Type u_2} [preorder α] [preorder β] (f : preorder_hom α β) :

@[instance]

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def Preorder.​of (α : Type u_1) [preorder α] :

Construct a bundled Preorder from the underlying type and typeclass.

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@[instance]

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