Theorem: Ordinal.sup_le_sup
File: Mathlib/SetTheory/Ordinal/Arithmetic.lean

tactic: cases'
  typein_surj r'
    (by
      rw [ho', ← ho]
      exact typein_lt_type r i) with
  j hj
state_before: α : Type u_1
β : Type u_2
γ : Type u_3
r✝ : α → α → Prop
s : β → β → Prop
t : γ → γ → Prop
ι ι' : Type u
r : ι → ι → Prop
r' : ι' → ι' → Prop
inst✝¹ : IsWellOrder ι r
inst✝ : IsWellOrder ι' r'
o : Ordinal.{u}
ho : type r = o
ho' : type r' = o
f : (a : Ordinal.{u}) → a < o → Ordinal.{max u v}
i : ι
⊢ familyOfBFamily' r ho f i ≤ sup (familyOfBFamily' r' ho' f)
state_after: case intro
α : Type u_1
β : Type u_2
γ : Type u_3
r✝ : α → α → Prop
s : β → β → Prop
t : γ → γ → Prop
ι ι' : Type u
r : ι → ι → Prop
r' : ι' → ι' → Prop
inst✝¹ : IsWellOrder ι r
inst✝ : IsWellOrder ι' r'
o : Ordinal.{u}
ho : type r = o
ho' : type r' = o
f : (a : Ordinal.{u}) → a < o → Ordinal.{max u v}
i : ι
j : ι'
hj : typein r' j = typein r i
⊢ familyOfBFamily' r ho f i ≤ sup (familyOfBFamily' r' ho' f)

tactic: simp_rw [familyOfBFamily', ← hj]
state_before: case intro
α : Type u_1
β : Type u_2
γ : Type u_3
r✝ : α → α → Prop
s : β → β → Prop
t : γ → γ → Prop
ι ι' : Type u
r : ι → ι → Prop
r' : ι' → ι' → Prop
inst✝¹ : IsWellOrder ι r
inst✝ : IsWellOrder ι' r'
o : Ordinal.{u}
ho : type r = o
ho' : type r' = o
f : (a : Ordinal.{u}) → a < o → Ordinal.{max u v}
i : ι
j : ι'
hj : typein r' j = typein r i
⊢ familyOfBFamily' r ho f i ≤ sup (familyOfBFamily' r' ho' f)
state_after: case intro
α : Type u_1
β : Type u_2
γ : Type u_3
r✝ : α → α → Prop
s : β → β → Prop
t : γ → γ → Prop
ι ι' : Type u
r : ι → ι → Prop
r' : ι' → ι' → Prop
inst✝¹ : IsWellOrder ι r
inst✝ : IsWellOrder ι' r'
o : Ordinal.{u}
ho : type r = o
ho' : type r' = o
f : (a : Ordinal.{u}) → a < o → Ordinal.{max u v}
i : ι
j : ι'
hj : typein r' j = typein r i
⊢ f (typein r' j) ⋯ ≤ sup (familyOfBFamily' r' ho' f)

tactic: apply le_sup
state_before: case intro
α : Type u_1
β : Type u_2
γ : Type u_3
r✝ : α → α → Prop
s : β → β → Prop
t : γ → γ → Prop
ι ι' : Type u
r : ι → ι → Prop
r' : ι' → ι' → Prop
inst✝¹ : IsWellOrder ι r
inst✝ : IsWellOrder ι' r'
o : Ordinal.{u}
ho : type r = o
ho' : type r' = o
f : (a : Ordinal.{u}) → a < o → Ordinal.{max u v}
i : ι
j : ι'
hj : typein r' j = typein r i
⊢ f (typein r' j) ⋯ ≤ sup (familyOfBFamily' r' ho' f)
state_after: no goals

tactic: rw [ho', ← ho]
state_before: α : Type u_1
β : Type u_2
γ : Type u_3
r✝ : α → α → Prop
s : β → β → Prop
t : γ → γ → Prop
ι ι' : Type u
r : ι → ι → Prop
r' : ι' → ι' → Prop
inst✝¹ : IsWellOrder ι r
inst✝ : IsWellOrder ι' r'
o : Ordinal.{u}
ho : type r = o
ho' : type r' = o
f : (a : Ordinal.{u}) → a < o → Ordinal.{max u v}
i : ι
⊢ ?m.185728 < type r'
state_after: α : Type u_1
β : Type u_2
γ : Type u_3
r✝ : α → α → Prop
s : β → β → Prop
t : γ → γ → Prop
ι ι' : Type u
r : ι → ι → Prop
r' : ι' → ι' → Prop
inst✝¹ : IsWellOrder ι r
inst✝ : IsWellOrder ι' r'
o : Ordinal.{u}
ho : type r = o
ho' : type r' = o
f : (a : Ordinal.{u}) → a < o → Ordinal.{max u v}
i : ι
⊢ ?m.185728 < type r

tactic: exact typein_lt_type r i
state_before: α : Type u_1
β : Type u_2
γ : Type u_3
r✝ : α → α → Prop
s : β → β → Prop
t : γ → γ → Prop
ι ι' : Type u
r : ι → ι → Prop
r' : ι' → ι' → Prop
inst✝¹ : IsWellOrder ι r
inst✝ : IsWellOrder ι' r'
o : Ordinal.{u}
ho : type r = o
ho' : type r' = o
f : (a : Ordinal.{u}) → a < o → Ordinal.{max u v}
i : ι
⊢ ?m.185728 < type r
state_after: no goals