Set: pp::colors
  Set: pp::unicode
⊤
  Set: lean::pp::notation
and ⊤ ⊥
  Set: pp::unicode
and true false
  Assumed: a
ex2.lean:8:0: error: invalid object declaration, environment already has an object named 'a'
  Assumed: b
and a b
  Assumed: A
ex2.lean:12:8: error: type mismatch at application
    and a A
Function type:
    Bool -> Bool -> Bool
Arguments types:
    a : Bool
    A : Type
variable A : Type
(lean::pp::notation := false, pp::unicode := false, pp::colors := false)
ex2.lean:15:11: error: unknown option 'lean::p::notation', type 'Help Options.' for list of available options
ex2.lean:16:30: error: invalid option value, given option is not an integer
  Set: lean::pp::notation
a /\ b