src/RMCA/Auxiliary/Misc.hs

   1 module RMCA.Auxiliary.Misc where
   2
   3 import Data.Maybe
   4 import FRP.Yampa
   5
   6 -- |= General functions
   7
   8
   9 {-
  10 -- | Reversed version of '(\<$\>)'.
  11 (<$$>) :: (Functor f) => f a -> (a -> b) -> f b
  12 (<$$>) = flip (<$>)
  13
  14 -- | Reversed version of '(<$)'.
  15 ($>) :: (Functor f) => f a -> b -> f b
  16 ($>) = flip (<$)
  17 -}
  18
  19 -- | @bound (min,max)@ behaves like identity if the supplied value is between @min@ and @max@, otherwise it is replaced either by @min@ or by @max@.
  20 bound :: (Ord a) => (a, a) -> a -> a
  21 bound (min, max) x
  22   | x < min = min
  23   | x > max = max
  24   | otherwise = x
  25
  26 fromMaybeM_ :: (Monad m) => Maybe (m ()) -> m ()
  27 fromMaybeM_ = fromMaybe (return ())
  28
  29 safeHead :: [a] -> Maybe a
  30 safeHead [] = Nothing
  31 safeHead (x:_) = Just x
  32
  33 safeTail :: [a] -> [a]
  34 safeTail [] = []
  35 safeTail (_:xs) = xs
  36
  37 maybeToEvent :: Maybe a -> Event a
  38 maybeToEvent Nothing = NoEvent
  39 maybeToEvent (Just x) = Event x
  40
  41 eventToMaybe :: Event a -> Maybe a
  42 eventToMaybe NoEvent = Nothing
  43 eventToMaybe (Event x) = Just x
  44
  45 eventToList :: Event [a] -> [a]
  46 eventToList NoEvent = []
  47 eventToList (Event x) = x
  48
  49 -- | Generates an 'Event' if the given condition is 'True'.
  50 eventIf :: Bool -> Event ()
  51 eventIf b = if b then Event () else NoEvent
  52
  53 -- | Generates a 'Just' value if the given condition is 'True'.
  54 maybeIf :: Bool -> Maybe ()
  55 maybeIf b = if b then Just () else Nothing
  56
  57 curry3 :: ((a,b,c) -> d) -> a -> b -> c -> d
  58 curry3 f a b c = f (a,b,c)
  59
  60 uncurry3 :: (a -> b -> c -> d) -> (a,b,c) -> d
  61 uncurry3 f (a,b,c) = f a b c
  62
  63 curry4 :: ((a,b,c,d) -> e) -> a -> b -> c -> d -> e
  64 curry4 f a b c d = f (a,b,c,d)
  65
  66 uncurry4 :: (a -> b -> c -> d -> e) -> (a,b,c,d) -> e
  67 uncurry4 f (a,b,c,d) = f a b c d
  68
  69 curry5 :: ((a,b,c,d,e) -> f) -> a -> b -> c -> d -> e -> f
  70 curry5 f a b c d e = f (a,b,c,d,e)
  71
  72 uncurry5 :: (a -> b -> c -> d -> e -> f) -> (a,b,c,d,e) -> f
  73 uncurry5 f (a,b,c,d,e) = f a b c d e