Module: Mathlib.Order.Std

Goal state before:
pp: case pos
α : Type u_1
args : OfStdArgs α
this✝⁷ : LE α := args.le
this✝⁶ : LT α := args.lt
this✝⁵ :
  let this := args.le;
  let this_1 := args.lt;
  Std.LawfulOrderLT α
this✝⁴ :
  let this := args.le;
  Std.IsLinearOrder α
this✝³ : DecidableLE α := args.decidableLE
this✝² : Std.LawfulOrderLeftLeaningMin α
this✝¹ : Std.LawfulOrderLeftLeaningMax α
a b : α
this✝ : Ord α := args.ord
this :
  let this := args.le;
  let this_1 := args.lt;
  let this_2 := ⋯;
  let this_3 := ⋯;
  let this_4 := args.decidableEq;
  let this_5 := args.decidableLT;
  Std.LawfulOrderOrd α
h✝ : a < b
⊢ compare a b = Ordering.lt

pp: case pos
α : Type u_1
args : OfStdArgs α
this✝⁷ : LE α := args.le
this✝⁶ : LT α := args.lt
this✝⁵ :
  let this := args.le;
  let this_1 := args.lt;
  Std.LawfulOrderLT α
this✝⁴ :
  let this := args.le;
  Std.IsLinearOrder α
this✝³ : DecidableLE α := args.decidableLE
this✝² : Std.LawfulOrderLeftLeaningMin α
this✝¹ : Std.LawfulOrderLeftLeaningMax α
a b : α
this✝ : Ord α := args.ord
this :
  let this := args.le;
  let this_1 := args.lt;
  let this_2 := ⋯;
  let this_3 := ⋯;
  let this_4 := args.decidableEq;
  let this_5 := args.decidableLT;
  Std.LawfulOrderOrd α
h✝¹ : ¬a < b
h✝ : a = b
⊢ compare a b = Ordering.eq

pp: case neg
α : Type u_1
args : OfStdArgs α
this✝⁷ : LE α := args.le
this✝⁶ : LT α := args.lt
this✝⁵ :
  let this := args.le;
  let this_1 := args.lt;
  Std.LawfulOrderLT α
this✝⁴ :
  let this := args.le;
  Std.IsLinearOrder α
this✝³ : DecidableLE α := args.decidableLE
this✝² : Std.LawfulOrderLeftLeaningMin α
this✝¹ : Std.LawfulOrderLeftLeaningMax α
a b : α
this✝ : Ord α := args.ord
this :
  let this := args.le;
  let this_1 := args.lt;
  let this_2 := ⋯;
  let this_3 := ⋯;
  let this_4 := args.decidableEq;
  let this_5 := args.decidableLT;
  Std.LawfulOrderOrd α
h✝¹ : ¬a < b
h✝ : ¬a = b
⊢ compare a b = Ordering.gt

Tactic:
case _ => rwa [Std.compare_eq_lt]

Goal state after:
case pos
α : Type u_1
args : OfStdArgs α
this✝⁷ : LE α := args.le
this✝⁶ : LT α := args.lt
this✝⁵ :
  let this := args.le;
  let this_1 := args.lt;
  Std.LawfulOrderLT α
this✝⁴ :
  let this := args.le;
  Std.IsLinearOrder α
this✝³ : DecidableLE α := args.decidableLE
this✝² : Std.LawfulOrderLeftLeaningMin α
this✝¹ : Std.LawfulOrderLeftLeaningMax α
a b : α
this✝ : Ord α := args.ord
this :
  let this := args.le;
  let this_1 := args.lt;
  let this_2 := ⋯;
  let this_3 := ⋯;
  let this_4 := args.decidableEq;
  let this_5 := args.decidableLT;
  Std.LawfulOrderOrd α
h✝¹ : ¬a < b
h✝ : a = b
⊢ compare a b = Ordering.eq

case neg
α : Type u_1
args : OfStdArgs α
this✝⁷ : LE α := args.le
this✝⁶ : LT α := args.lt
this✝⁵ :
  let this := args.le;
  let this_1 := args.lt;
  Std.LawfulOrderLT α
this✝⁴ :
  let this := args.le;
  Std.IsLinearOrder α
this✝³ : DecidableLE α := args.decidableLE
this✝² : Std.LawfulOrderLeftLeaningMin α
this✝¹ : Std.LawfulOrderLeftLeaningMax α
a b : α
this✝ : Ord α := args.ord
this :
  let this := args.le;
  let this_1 := args.lt;
  let this_2 := ⋯;
  let this_3 := ⋯;
  let this_4 := args.decidableEq;
  let this_5 := args.decidableLT;
  Std.LawfulOrderOrd α
h✝¹ : ¬a < b
h✝ : ¬a = b
⊢ compare a b = Ordering.gt