a : Nat

prvCtor.lean:21:7-21:8: error: unknown identifier 'a'
prvCtor.lean:23:25-23:27: error: overloaded, errors 
  failed to synthesize instance
    EmptyCollection (Name "hello")
  
  invalid {...} notation, constructor for `Name` is marked as private
prvCtor.lean:25:25-25:34: error: invalid ⟨...⟩ notation, constructor for `Name` is marked as private
prvCtor.lean:27:25-27:40: error: unknown constant 'Name.mk'