prettyPreAcc pp alvl wrap (Scanl1 f acc)
  = wrap 
  $ prettyArrOp "scanl1" [parens (prettyPreFun pp alvl f), pp alvl parens acc]
prettyPreAcc pp alvl wrap (Scanl1 f acc)
  = wrap 
  $ prettyArrOp "scanl1" [parens (prettyPreFun pp alvl f), pp alvl parens acc]
prettyPreAcc pp alvl wrap (Scanl1 f acc)
  = wrap 
  $ prettyArrOp "scanl1" [parens (prettyPreFun pp alvl f), pp alvl parens acc]