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module T11397 where
f :: a -> [Maybe a]
f x =
let switch l = [l Nothing, l (Just x)]
in switch id
u :: a
u = u
f2 :: a
f2 = let switch l = l u in switch u
f3 :: a
f3 = let switch l = l undefined in switch undefined
newtype VectorLazy a = VectorLazy a
newtype Vector a = Vector a
newtype Pointer a = Pointer a
empty :: VectorLazy a
empty = undefined
cons :: Vector a -> Pointer a
cons = undefined
unfoldrResult :: (a -> Either c (b, a)) -> a -> (VectorLazy b, c)
unfoldrResult = undefined
switchL :: b -> (a -> Pointer a -> b) -> Pointer a -> b
switchL = undefined
inverseFrequencyModulationChunk ::
(Num t, Ord t) =>
(s -> Maybe (t,s)) -> (t,s) -> Vector v -> (VectorLazy v, Maybe (t,s))
inverseFrequencyModulationChunk nextC (phase,cst0) chunk =
let {-
switch ::
(Maybe (t, s) -> r) ->
((t, v) -> (s, Pointer v) -> r) ->
t ->
(s, Pointer v) -> r
-}
switch l r t (cp0,xp0) =
maybe
(l Nothing)
(\(c1,cp1) ->
switchL
(l (Just (t,cp0)))
(\x1 xp1 -> r (t+c1,x1) (cp1,xp1))
xp0)
(nextC cp0)
{-
go ::
(t,v) -> (s, Pointer v) ->
Either (Maybe (t,s)) (v, ((t,v), (s, Pointer v)))
-}
go (c,x) cxp =
if c<1
then switch Left go c cxp
else Right (x, ((c-1,x),cxp))
in switch ((,) empty)
(curry $ unfoldrResult (uncurry go))
phase (cst0, cons chunk)
|
