
<interactive>:5:1: error:
    No instance for (Show t1) arising from a use of ‘print’
    Cannot resolve unknown runtime type ‘t1’
    Use :print or :force to determine these types
    Relevant bindings include it :: t1 (bound at <interactive>:5:1)
    These potential instances exist:
      instance (Show a, Show b) => Show (Either a b)
        -- Defined in ‘Data.Either’
      instance Show All -- Defined in ‘Data.Monoid’
      instance forall (k :: BOX) (f :: k -> *) (a :: k).
               Show (f a) =>
               Show (Alt f a)
        -- Defined in ‘Data.Monoid’
      ...plus 36 others
      (use -fprint-potential-instances to see them all)
    In a stmt of an interactive GHCi command: print it

<interactive>:7:1: error:
    No instance for (Show t1) arising from a use of ‘print’
    Cannot resolve unknown runtime type ‘t1’
    Use :print or :force to determine these types
    Relevant bindings include it :: t1 (bound at <interactive>:7:1)
    These potential instances exist:
      instance (Show a, Show b) => Show (Either a b)
        -- Defined in ‘Data.Either’
      instance Show All -- Defined in ‘Data.Monoid’
      instance forall (k :: BOX) (f :: k -> *) (a :: k).
               Show (f a) =>
               Show (Alt f a)
        -- Defined in ‘Data.Monoid’
      ...plus 36 others
      (use -fprint-potential-instances to see them all)
    In a stmt of an interactive GHCi command: print it