Module: Mathlib.CategoryTheory.WithTerminal.Basic

Goal state before:
pp: case of.of
C : Type u
inst✝¹ : Category.{v, u} C
D : Type u_1
inst✝ : Category.{v_1, u_1} D
Z : D
F : C ⥤ D
M : (x : C) → F.obj x ⟶ Z
hM : ∀ (x y : C) (f : x ⟶ y), F.map f ≫ M y = M x
G : WithTerminal C ⥤ D
h : incl ⋙ G ≅ F
hG : G.obj star ≅ Z
hh : ∀ (x : C), G.map (starTerminal.from (incl.obj x)) ≫ hG.hom = h.hom.app x ≫ M x
X Y : C
f : of X ⟶ of Y
⊢ G.map f ≫
      (match of Y with
        | of x => h.app x
        | star => hG).hom =
    (match of X with
        | of x => h.app x
        | star => hG).hom ≫
      (lift F M hM).map f

pp: case of.star
C : Type u
inst✝¹ : Category.{v, u} C
D : Type u_1
inst✝ : Category.{v_1, u_1} D
Z : D
F : C ⥤ D
M : (x : C) → F.obj x ⟶ Z
hM : ∀ (x y : C) (f : x ⟶ y), F.map f ≫ M y = M x
G : WithTerminal C ⥤ D
h : incl ⋙ G ≅ F
hG : G.obj star ≅ Z
hh : ∀ (x : C), G.map (starTerminal.from (incl.obj x)) ≫ hG.hom = h.hom.app x ≫ M x
X : C
f : of X ⟶ star
⊢ G.map f ≫
      (match star with
        | of x => h.app x
        | star => hG).hom =
    (match of X with
        | of x => h.app x
        | star => hG).hom ≫
      (lift F M hM).map f

pp: case star.of
C : Type u
inst✝¹ : Category.{v, u} C
D : Type u_1
inst✝ : Category.{v_1, u_1} D
Z : D
F : C ⥤ D
M : (x : C) → F.obj x ⟶ Z
hM : ∀ (x y : C) (f : x ⟶ y), F.map f ≫ M y = M x
G : WithTerminal C ⥤ D
h : incl ⋙ G ≅ F
hG : G.obj star ≅ Z
hh : ∀ (x : C), G.map (starTerminal.from (incl.obj x)) ≫ hG.hom = h.hom.app x ≫ M x
Y : C
f : star ⟶ of Y
⊢ G.map f ≫
      (match of Y with
        | of x => h.app x
        | star => hG).hom =
    (match star with
        | of x => h.app x
        | star => hG).hom ≫
      (lift F M hM).map f

pp: case star.star
C : Type u
inst✝¹ : Category.{v, u} C
D : Type u_1
inst✝ : Category.{v_1, u_1} D
Z : D
F : C ⥤ D
M : (x : C) → F.obj x ⟶ Z
hM : ∀ (x y : C) (f : x ⟶ y), F.map f ≫ M y = M x
G : WithTerminal C ⥤ D
h : incl ⋙ G ≅ F
hG : G.obj star ≅ Z
hh : ∀ (x : C), G.map (starTerminal.from (incl.obj x)) ≫ hG.hom = h.hom.app x ≫ M x
f : star ⟶ star
⊢ G.map f ≫
      (match star with
        | of x => h.app x
        | star => hG).hom =
    (match star with
        | of x => h.app x
        | star => hG).hom ≫
      (lift F M hM).map f

Tactic:
· apply h.hom.naturality

Goal state after:
case of.star
C : Type u
inst✝¹ : Category.{v, u} C
D : Type u_1
inst✝ : Category.{v_1, u_1} D
Z : D
F : C ⥤ D
M : (x : C) → F.obj x ⟶ Z
hM : ∀ (x y : C) (f : x ⟶ y), F.map f ≫ M y = M x
G : WithTerminal C ⥤ D
h : incl ⋙ G ≅ F
hG : G.obj star ≅ Z
hh : ∀ (x : C), G.map (starTerminal.from (incl.obj x)) ≫ hG.hom = h.hom.app x ≫ M x
X : C
f : of X ⟶ star
⊢ G.map f ≫
      (match star with
        | of x => h.app x
        | star => hG).hom =
    (match of X with
        | of x => h.app x
        | star => hG).hom ≫
      (lift F M hM).map f

case star.of
C : Type u
inst✝¹ : Category.{v, u} C
D : Type u_1
inst✝ : Category.{v_1, u_1} D
Z : D
F : C ⥤ D
M : (x : C) → F.obj x ⟶ Z
hM : ∀ (x y : C) (f : x ⟶ y), F.map f ≫ M y = M x
G : WithTerminal C ⥤ D
h : incl ⋙ G ≅ F
hG : G.obj star ≅ Z
hh : ∀ (x : C), G.map (starTerminal.from (incl.obj x)) ≫ hG.hom = h.hom.app x ≫ M x
Y : C
f : star ⟶ of Y
⊢ G.map f ≫
      (match of Y with
        | of x => h.app x
        | star => hG).hom =
    (match star with
        | of x => h.app x
        | star => hG).hom ≫
      (lift F M hM).map f

case star.star
C : Type u
inst✝¹ : Category.{v, u} C
D : Type u_1
inst✝ : Category.{v_1, u_1} D
Z : D
F : C ⥤ D
M : (x : C) → F.obj x ⟶ Z
hM : ∀ (x y : C) (f : x ⟶ y), F.map f ≫ M y = M x
G : WithTerminal C ⥤ D
h : incl ⋙ G ≅ F
hG : G.obj star ≅ Z
hh : ∀ (x : C), G.map (starTerminal.from (incl.obj x)) ≫ hG.hom = h.hom.app x ≫ M x
f : star ⟶ star
⊢ G.map f ≫
      (match star with
        | of x => h.app x
        | star => hG).hom =
    (match star with
        | of x => h.app x
        | star => hG).hom ≫
      (lift F M hM).map f