
<interactive>:1:1: error:
    • Found hole: _ :: t
      Where: ‘t’ is a rigid type variable bound by
               the inferred type of it :: t at <interactive>:1:1
    • In the expression: _
      In an equation for ‘it’: it = _
    • Relevant bindings include it :: t (bound at <interactive>:1:1)
      Valid substitutions include
        undefined :: forall (a :: TYPE r).
                     GHC.Stack.Types.HasCallStack =>
                     a
          (imported from ‘Prelude’ (and originally defined in ‘GHC.Err’))