[Haskell-cafe] unfoldr with a little extra

[David Feuer]

Edward Kmett's NonEmpty module has a version of unfoldr (there just called
unfoldr) for non-empty lists that seems also to be useful when applied to
regular lists:

unfoldr1::(b -> (a, Maybe b)) -> b -> [a]
unfoldr1 f b= go b
  where
    go q = case f q of
      (a,may_b) -> a : maybe [] go may_b

My question is whether it is possible to write this function using the
usual unfoldr. I have the feeling there might be some way, but I just can't
see it.

David
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