set_option linter.missingDocs false

example (a : Nat) : a = a := rfl

example (a : Nat) : a = a := by rfl

open Setoid

universe u
variable {α : Sort u} [Setoid α]

@[refl] def iseqv_refl (a : α) : a ≈ a :=
  iseqv.refl a

example (a : α) : a ≈ a := by rfl

example (a : Nat) : a ≤ a := by (fail_if_success rfl); apply Nat.le_refl

attribute [refl] Nat.le_refl

example (a : Nat) : a ≤ a := by rfl

structure Foo

def Foo.le (_ _ : Foo) := Unit → True
instance : LE Foo := ⟨Foo.le⟩

@[refl] theorem Foo.le_refl (a : Foo) : a ≤ a := fun _ => trivial

example (a : Foo) : a ≤ a := by apply Foo.le_refl
example (a : Foo) : a ≤ a := by rfl

example (x : Nat) : x ≤ x := by
  show _
  rfl