3 Couldn't match expected type ‘a’ with actual type ‘HsDoc t0’
4 ‘a’ is a rigid type variable bound by
6 gfoldl' :: (forall a1 b. c (a1 -> b) -> a1 -> c b)
7 -> (forall g. g -> c g) -> a -> c a
9 Relevant bindings include
10 hsDoc :: a (bound at tcfail201.hs:16:13)
11 gfoldl' :: (forall a1 b. c (a1 -> b) -> a1 -> c b)
12 -> (forall g. g -> c g) -> a -> c a
13 (bound at tcfail201.hs:16:1)
14 In the pattern: DocEmpty
15 In a case alternative: DocEmpty -> z DocEmpty
18 DocEmpty -> z DocEmpty
19 (DocParagraph hsDoc) -> z DocParagraph `k` hsDoc }