Module: Mathlib.Data.Ordmap.Ordset

Goal state before:
pp: case node.lt
α : Type u_1
inst✝¹ : Preorder α
inst✝ : DecidableLE α
x : α
size✝ : ℕ
t_l : Ordnode α
t_x : α
t_r : Ordnode α
a₁ : WithBot α
a₂ : WithTop α
h : Valid' a₁ (node size✝ t_l t_x t_r) a₂
t_ih_l' : x ∈ t_l → (erase x t_l).size = t_l.size - 1
t_ih_r' : x ∈ t_r → (erase x t_r).size = t_r.size - 1
⊢ (match Ordering.lt with
      | Ordering.lt => mem x t_l
      | Ordering.eq => true
      | Ordering.gt => mem x t_r) =
      true →
    (match Ordering.lt with
        | Ordering.lt => (erase x t_l).balanceR t_x t_r
        | Ordering.eq => t_l.glue t_r
        | Ordering.gt => t_l.balanceL t_x (erase x t_r)).size =
      (node size✝ t_l t_x t_r).size - 1

pp: case node.eq
α : Type u_1
inst✝¹ : Preorder α
inst✝ : DecidableLE α
x : α
size✝ : ℕ
t_l : Ordnode α
t_x : α
t_r : Ordnode α
a₁ : WithBot α
a₂ : WithTop α
h : Valid' a₁ (node size✝ t_l t_x t_r) a₂
t_ih_l' : x ∈ t_l → (erase x t_l).size = t_l.size - 1
t_ih_r' : x ∈ t_r → (erase x t_r).size = t_r.size - 1
⊢ (match Ordering.eq with
      | Ordering.lt => mem x t_l
      | Ordering.eq => true
      | Ordering.gt => mem x t_r) =
      true →
    (match Ordering.eq with
        | Ordering.lt => (erase x t_l).balanceR t_x t_r
        | Ordering.eq => t_l.glue t_r
        | Ordering.gt => t_l.balanceL t_x (erase x t_r)).size =
      (node size✝ t_l t_x t_r).size - 1

pp: case node.gt
α : Type u_1
inst✝¹ : Preorder α
inst✝ : DecidableLE α
x : α
size✝ : ℕ
t_l : Ordnode α
t_x : α
t_r : Ordnode α
a₁ : WithBot α
a₂ : WithTop α
h : Valid' a₁ (node size✝ t_l t_x t_r) a₂
t_ih_l' : x ∈ t_l → (erase x t_l).size = t_l.size - 1
t_ih_r' : x ∈ t_r → (erase x t_r).size = t_r.size - 1
⊢ (match Ordering.gt with
      | Ordering.lt => mem x t_l
      | Ordering.eq => true
      | Ordering.gt => mem x t_r) =
      true →
    (match Ordering.gt with
        | Ordering.lt => (erase x t_l).balanceR t_x t_r
        | Ordering.eq => t_l.glue t_r
        | Ordering.gt => t_l.balanceL t_x (erase x t_r)).size =
      (node size✝ t_l t_x t_r).size - 1

Tactic:
<;>

Goal state after:
case node.lt
α : Type u_1
inst✝¹ : Preorder α
inst✝ : DecidableLE α
x : α
size✝ : ℕ
t_l : Ordnode α
t_x : α
t_r : Ordnode α
a₁ : WithBot α
a₂ : WithTop α
h : Valid' a₁ (node size✝ t_l t_x t_r) a₂
t_ih_l' : x ∈ t_l → (erase x t_l).size = t_l.size - 1
t_ih_r' : x ∈ t_r → (erase x t_r).size = t_r.size - 1
⊢ (match Ordering.lt with
      | Ordering.lt => mem x t_l
      | Ordering.eq => true
      | Ordering.gt => mem x t_r) =
      true →
    (match Ordering.lt with
        | Ordering.lt => (erase x t_l).balanceR t_x t_r
        | Ordering.eq => t_l.glue t_r
        | Ordering.gt => t_l.balanceL t_x (erase x t_r)).size =
      (node size✝ t_l t_x t_r).size - 1

case node.eq
α : Type u_1
inst✝¹ : Preorder α
inst✝ : DecidableLE α
x : α
size✝ : ℕ
t_l : Ordnode α
t_x : α
t_r : Ordnode α
a₁ : WithBot α
a₂ : WithTop α
h : Valid' a₁ (node size✝ t_l t_x t_r) a₂
t_ih_l' : x ∈ t_l → (erase x t_l).size = t_l.size - 1
t_ih_r' : x ∈ t_r → (erase x t_r).size = t_r.size - 1
⊢ (match Ordering.eq with
      | Ordering.lt => mem x t_l
      | Ordering.eq => true
      | Ordering.gt => mem x t_r) =
      true →
    (match Ordering.eq with
        | Ordering.lt => (erase x t_l).balanceR t_x t_r
        | Ordering.eq => t_l.glue t_r
        | Ordering.gt => t_l.balanceL t_x (erase x t_r)).size =
      (node size✝ t_l t_x t_r).size - 1

case node.gt
α : Type u_1
inst✝¹ : Preorder α
inst✝ : DecidableLE α
x : α
size✝ : ℕ
t_l : Ordnode α
t_x : α
t_r : Ordnode α
a₁ : WithBot α
a₂ : WithTop α
h : Valid' a₁ (node size✝ t_l t_x t_r) a₂
t_ih_l' : x ∈ t_l → (erase x t_l).size = t_l.size - 1
t_ih_r' : x ∈ t_r → (erase x t_r).size = t_r.size - 1
⊢ (match Ordering.gt with
      | Ordering.lt => mem x t_l
      | Ordering.eq => true
      | Ordering.gt => mem x t_r) =
      true →
    (match Ordering.gt with
        | Ordering.lt => (erase x t_l).balanceR t_x t_r
        | Ordering.eq => t_l.glue t_r
        | Ordering.gt => t_l.balanceL t_x (erase x t_r)).size =
      (node size✝ t_l t_x t_r).size - 1