prettyPreAcc pp alvl wrap (Scanl f e acc)
  = wrap 
  $ prettyArrOp "scanl" [parens (prettyPreFun pp alvl f), prettyPreExp pp 0 alvl parens e,
                         pp alvl parens acc]
prettyPreAcc pp alvl wrap (Scanl f e acc)
  = wrap 
  $ prettyArrOp "scanl" [parens (prettyPreFun pp alvl f), prettyPreExp pp 0 alvl parens e,
                         pp alvl parens acc]
prettyPreAcc pp alvl wrap (Scanl f e acc)
  = wrap 
  $ prettyArrOp "scanl" [parens (prettyPreFun pp alvl f), prettyPreExp pp 0 alvl parens e,
                         pp alvl parens acc]