fillIn.hs

import Sound.Tidal.Utils

let fillIn p' p = struct (splitQueries $ Pattern (f p)) p'
    f p (s,e) = removeTolerance (s,e) $ invert (s-tolerance, e+tolerance) $ arc p (s-tolerance, e+tolerance)
    invert (s,e) es = map arcToEvent $ foldr remove [(s,e)] (map snd' es)
    remove (s,e) xs = concatMap (remove' (s, e)) xs
    remove' (s,e) (s',e') | s > s' && e < e' = [(s',s),(e,e')] -- inside
                          | s > s' && s < e' = [(s',s)] -- cut off right
                          | e > s' && e < e' = [(e,e')] -- cut off left
                          | s <= s' && e >= e' = [] -- swallow
                          | otherwise = [(s',e')] -- miss
    arcToEvent a = (a,a,"x")
    removeTolerance (s,e) es = concatMap (expand) $ mapSnds' f es
      where f (a) = concatMap (remove' (e,e+tolerance)) $ remove' (s-tolerance,s) a
            expand (a,xs,c) = map (\x -> (a,x,c)) xs
    tolerance = 0.01


d1 $ (n $ every 4 (fillIn "4") "0 [~ 5] ~ [3 ~] ~ 2 [5 ~]") # s "feel"
  # speed 2