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T14172.hs:6:46: error:
    • Found type wildcard ‘_’ standing for ‘a'’
      Where: ‘a'’ is a rigid type variable bound by
               the inferred type of
                 traverseCompose :: (a -> f b) -> g a -> f (h a')
               at T14172.hs:7:1-46
      To use the inferred type, enable PartialTypeSignatures
    • In the first argument of ‘h’, namely ‘_’
      In the first argument of ‘f’, namely ‘(h _)’
      In the type ‘(a -> f b) -> g a -> f (h _)’

T14172.hs:7:19: error:
    • Occurs check: cannot construct the infinite type: a ~ g'1 a
      Expected type: (f'0 a -> f (f'0 b))
                     -> Compose f'0 g'1 a -> f (h a')
        Actual type: (Unwrapped (Compose f'0 g'1 a)
                      -> f (Unwrapped (h a')))
                     -> Compose f'0 g'1 a -> f (h a')
    • In the first argument of ‘(.)’, namely ‘_Wrapping Compose’
      In the expression: _Wrapping Compose . traverse
      In an equation for ‘traverseCompose’:
          traverseCompose = _Wrapping Compose . traverse
    • Relevant bindings include
        traverseCompose :: (a -> f b) -> g a -> f (h a')
          (bound at T14172.hs:7:1)