Digraph.hs:19: A type signature is more polymorphic than the inferred type
		   Some type variables in the inferred type can't be forall'd, namely:
		   `taXO'
		   Possible cause: the RHS mentions something subject to the monomorphism restriction
    When checking signature for `reversed_edges'
    In an equation for function `stronglyConnComp':
	`stronglyConnComp es vs
			  = PrelTup.snd (span_tree (new_range reversed_edges)
						   (PrelBase.[], (PrelBase.[]))
						   (PrelTup.snd (dfs (new_range es)
								     (PrelBase.[], (PrelBase.[]))
								     vs)))
			  where
			      span_tree r (vs, ns) PrelBase.[] = (vs, (ns))
			      span_tree r (vs, ns) (x PrelBase.: xs)
					| [x PrelList.elem vs] = span_tree r (vs, (ns)) xs
					| [PrelBase.otherwise]
					= span_tree r (vs', ((x PrelBase.: ns') PrelBase.: ns)) xs
					where
					    (vs', ns')
						= dfs r (x PrelBase.: vs, (PrelBase.[])) (r x)
			      new_range PrelBase.[] w = PrelBase.[]
			      new_range ((x, y) PrelBase.: xys) w
					= if x PrelBase.== w then
					      (y PrelBase.: (new_range xys w))
					  else
					      (new_range xys w)
			      swap (x, y) = (y, (x))
			      reversed_edges :: _forall_ [v] (PrelBase.Eq v) => [Edge v]
			      reversed_edges = PrelBase.map swap es'


Compilation had errors