content: -- File generated by the BNF Converter (bnfc 2.9.6).
  
  {-# LANGUAGE CPP #-}
  {-# LANGUAGE FlexibleInstances #-}
  {-# LANGUAGE LambdaCase #-}
  
  -- | Pretty-printer for BNFC.
  
  module BNFC.Print where
  
  import Prelude
    ( ($), (.)
    , Bool(..), (==), (<)
    , Int, Integer, Double, (+), (-), (*)
    , String, (++)
    , ShowS, showChar, showString
    , all, elem, foldr, id, map, null, replicate, shows, span
    )
  import Data.Char ( Char, isSpace )
  import qualified BNFC.Abs
  
  -- | The top-level printing method.
  
  printTree :: Print a => a -> String
  printTree = render . prt 0
  
  type Doc = [ShowS] -> [ShowS]
  
  doc :: ShowS -> Doc
  doc = (:)
  
  render :: Doc -> String
  render d = rend 0 False (map ($ "") $ d []) ""
    where
    rend
      :: Int        -- ^ Indentation level.
      -> Bool       -- ^ Pending indentation to be output before next character?
      -> [String]
      -> ShowS
    rend i p = \case
        "["      :ts -> char '[' . rend i False ts
        "("      :ts -> char '(' . rend i False ts
        "{"      :ts -> onNewLine i     p . showChar   '{'  . new (i+1) ts
        "}" : ";":ts -> onNewLine (i-1) p . showString "};" . new (i-1) ts
        "}"      :ts -> onNewLine (i-1) p . showChar   '}'  . new (i-1) ts
        [";"]        -> char ';'
        ";"      :ts -> char ';' . new i ts
        t  : ts@(s:_) | closingOrPunctuation s
                     -> pending . showString t . rend i False ts
        t        :ts -> pending . space t      . rend i False ts
        []           -> id
      where
      -- Output character after pending indentation.
      char :: Char -> ShowS
      char c = pending . showChar c
  
      -- Output pending indentation.
      pending :: ShowS
      pending = if p then indent i else id
  
    -- Indentation (spaces) for given indentation level.
    indent :: Int -> ShowS
    indent i = replicateS (2*i) (showChar ' ')
  
    -- Continue rendering in new line with new indentation.
    new :: Int -> [String] -> ShowS
    new j ts = showChar '\n' . rend j True ts
  
    -- Make sure we are on a fresh line.
    onNewLine :: Int -> Bool -> ShowS
    onNewLine i p = (if p then id else showChar '\n') . indent i
  
    -- Separate given string from following text by a space (if needed).
    space :: String -> ShowS
    space t s =
      case (all isSpace t, null spc, null rest) of
        (True , _   , True ) -> []             -- remove trailing space
        (False, _   , True ) -> t              -- remove trailing space
        (False, True, False) -> t ++ ' ' : s   -- add space if none
        _                    -> t ++ s
      where
        (spc, rest) = span isSpace s
  
    closingOrPunctuation :: String -> Bool
    closingOrPunctuation [c] = c `elem` closerOrPunct
    closingOrPunctuation _   = False
  
    closerOrPunct :: String
    closerOrPunct = ")],;"
  
  parenth :: Doc -> Doc
  parenth ss = doc (showChar '(') . ss . doc (showChar ')')
  
  concatS :: [ShowS] -> ShowS
  concatS = foldr (.) id
  
  concatD :: [Doc] -> Doc
  concatD = foldr (.) id
  
  replicateS :: Int -> ShowS -> ShowS
  replicateS n f = concatS (replicate n f)
  
  -- | The printer class does the job.
  
  class Print a where
    prt :: Int -> a -> Doc
  
  instance {-# OVERLAPPABLE #-} Print a => Print [a] where
    prt i = concatD . map (prt i)
  
  instance Print Char where
    prt _ c = doc (showChar '\'' . mkEsc '\'' c . showChar '\'')
  
  instance Print String where
    prt _ = printString
  
  printString :: String -> Doc
  printString s = doc (showChar '"' . concatS (map (mkEsc '"') s) . showChar '"')
  
  mkEsc :: Char -> Char -> ShowS
  mkEsc q = \case
    s | s == q -> showChar '\\' . showChar s
    '\\' -> showString "\\\\"
    '\n' -> showString "\\n"
    '\t' -> showString "\\t"
    s -> showChar s
  
  prPrec :: Int -> Int -> Doc -> Doc
  prPrec i j = if j < i then parenth else id
  
  instance Print Integer where
    prt _ x = doc (shows x)
  
  instance Print Double where
    prt _ x = doc (shows x)
  
  instance Print BNFC.Abs.Identifier where
    prt _ (BNFC.Abs.Identifier (_,i)) = doc $ showString i
  instance Print BNFC.Abs.Grammar where
    prt i = \case
      BNFC.Abs.Grammar defs -> prPrec i 0 (concatD [prt 0 defs])
  
  instance Print [BNFC.Abs.Def] where
    prt _ [] = concatD []
    prt _ [x] = concatD [prt 0 x]
    prt _ (x:xs) = concatD [prt 0 x, doc (showString ";"), prt 0 xs]
  
  instance Print BNFC.Abs.Def where
    prt i = \case
      BNFC.Abs.Rule label cat items -> prPrec i 0 (concatD [prt 0 label, doc (showString "."), prt 0 cat, doc (showString "::="), prt 0 items])
      BNFC.Abs.Comment str -> prPrec i 0 (concatD [doc (showString "comment"), printString str])
      BNFC.Abs.Comments str1 str2 -> prPrec i 0 (concatD [doc (showString "comment"), printString str1, printString str2])
      BNFC.Abs.Internal label cat items -> prPrec i 0 (concatD [doc (showString "internal"), prt 0 label, doc (showString "."), prt 0 cat, doc (showString "::="), prt 0 items])
      BNFC.Abs.Token identifier reg -> prPrec i 0 (concatD [doc (showString "token"), prt 0 identifier, prt 0 reg])
      BNFC.Abs.PosToken identifier reg -> prPrec i 0 (concatD [doc (showString "position"), doc (showString "token"), prt 0 identifier, prt 0 reg])
      BNFC.Abs.Entryp cats -> prPrec i 0 (concatD [doc (showString "entrypoints"), prt 0 cats])
      BNFC.Abs.Separator minimumsize cat str -> prPrec i 0 (concatD [doc (showString "separator"), prt 0 minimumsize, prt 0 cat, printString str])
      BNFC.Abs.Terminator minimumsize cat str -> prPrec i 0 (concatD [doc (showString "terminator"), prt 0 minimumsize, prt 0 cat, printString str])
      BNFC.Abs.Delimiters cat str1 str2 separation minimumsize -> prPrec i 0 (concatD [doc (showString "delimiters"), prt 0 cat, printString str1, printString str2, prt 0 separation, prt 0 minimumsize])
      BNFC.Abs.Coercions identifier n -> prPrec i 0 (concatD [doc (showString "coercions"), prt 0 identifier, prt 0 n])
      BNFC.Abs.Rules identifier rhss -> prPrec i 0 (concatD [doc (showString "rules"), prt 0 identifier, doc (showString "::="), prt 0 rhss])
      BNFC.Abs.Function identifier args exp -> prPrec i 0 (concatD [doc (showString "define"), prt 0 identifier, prt 0 args, doc (showString "="), prt 0 exp])
      BNFC.Abs.Layout strs -> prPrec i 0 (concatD [doc (showString "layout"), prt 0 strs])
      BNFC.Abs.LayoutStop strs -> prPrec i 0 (concatD [doc (showString "layout"), doc (showString "stop"), prt 0 strs])
      BNFC.Abs.LayoutTop -> prPrec i 0 (concatD [doc (showString "layout"), doc (showString "toplevel")])
  
  instance Print BNFC.Abs.Item where
    prt i = \case
      BNFC.Abs.Terminal str -> prPrec i 0 (concatD [printString str])
      BNFC.Abs.NTerminal cat -> prPrec i 0 (concatD [prt 0 cat])
  
  instance Print [BNFC.Abs.Item] where
    prt _ [] = concatD []
    prt _ (x:xs) = concatD [prt 0 x, prt 0 xs]
  
  instance Print BNFC.Abs.Cat where
    prt i = \case
      BNFC.Abs.ListCat cat -> prPrec i 0 (concatD [doc (showString "["), prt 0 cat, doc (showString "]")])
      BNFC.Abs.IdCat identifier -> prPrec i 0 (concatD [prt 0 identifier])
  
  instance Print [BNFC.Abs.Cat] where
    prt _ [] = concatD []
    prt _ [x] = concatD [prt 0 x]
    prt _ (x:xs) = concatD [prt 0 x, doc (showString ","), prt 0 xs]
  
  instance Print BNFC.Abs.Label where
    prt i = \case
      BNFC.Abs.Id identifier -> prPrec i 0 (concatD [prt 0 identifier])
      BNFC.Abs.Wild -> prPrec i 0 (concatD [doc (showString "_")])
      BNFC.Abs.ListE -> prPrec i 0 (concatD [doc (showString "["), doc (showString "]")])
      BNFC.Abs.ListCons -> prPrec i 0 (concatD [doc (showString "("), doc (showString ":"), doc (showString ")")])
      BNFC.Abs.ListOne -> prPrec i 0 (concatD [doc (showString "("), doc (showString ":"), doc (showString "["), doc (showString "]"), doc (showString ")")])
  
  instance Print BNFC.Abs.Arg where
    prt i = \case
      BNFC.Abs.Arg identifier -> prPrec i 0 (concatD [prt 0 identifier])
  
  instance Print [BNFC.Abs.Arg] where
    prt _ [] = concatD []
    prt _ (x:xs) = concatD [prt 0 x, prt 0 xs]
  
  instance Print BNFC.Abs.Separation where
    prt i = \case
      BNFC.Abs.SepNone -> prPrec i 0 (concatD [])
      BNFC.Abs.SepTerm str -> prPrec i 0 (concatD [doc (showString "terminator"), printString str])
      BNFC.Abs.SepSepar str -> prPrec i 0 (concatD [doc (showString "separator"), printString str])
  
  instance Print [String] where
    prt _ [] = concatD []
    prt _ [x] = concatD [printString x]
    prt _ (x:xs) = concatD [printString x, doc (showString ","), prt 0 xs]
  
  instance Print BNFC.Abs.Exp where
    prt i = \case
      BNFC.Abs.Cons exp1 exp2 -> prPrec i 0 (concatD [prt 1 exp1, doc (showString ":"), prt 0 exp2])
      BNFC.Abs.App identifier exps -> prPrec i 1 (concatD [prt 0 identifier, prt 2 exps])
      BNFC.Abs.Var identifier -> prPrec i 2 (concatD [prt 0 identifier])
      BNFC.Abs.LitInt n -> prPrec i 2 (concatD [prt 0 n])
      BNFC.Abs.LitChar c -> prPrec i 2 (concatD [prt 0 c])
      BNFC.Abs.LitString str -> prPrec i 2 (concatD [printString str])
      BNFC.Abs.LitDouble d -> prPrec i 2 (concatD [prt 0 d])
      BNFC.Abs.List exps -> prPrec i 2 (concatD [doc (showString "["), prt 0 exps, doc (showString "]")])
  
  instance Print [BNFC.Abs.Exp] where
    prt 2 [x] = concatD [prt 2 x]
    prt 2 (x:xs) = concatD [prt 2 x, prt 2 xs]
    prt _ [] = concatD []
    prt _ [x] = concatD [prt 0 x]
    prt _ (x:xs) = concatD [prt 0 x, doc (showString ","), prt 0 xs]
  
  instance Print BNFC.Abs.RHS where
    prt i = \case
      BNFC.Abs.RHS items -> prPrec i 0 (concatD [prt 0 items])
  
  instance Print [BNFC.Abs.RHS] where
    prt _ [] = concatD []
    prt _ [x] = concatD [prt 0 x]
    prt _ (x:xs) = concatD [prt 0 x, doc (showString "|"), prt 0 xs]
  
  instance Print BNFC.Abs.MinimumSize where
    prt i = \case
      BNFC.Abs.MNonempty -> prPrec i 0 (concatD [doc (showString "nonempty")])
      BNFC.Abs.MEmpty -> prPrec i 0 (concatD [])
  
  instance Print BNFC.Abs.Reg where
    prt i = \case
      BNFC.Abs.RAlt reg1 reg2 -> prPrec i 0 (concatD [prt 0 reg1, doc (showString "|"), prt 1 reg2])
      BNFC.Abs.RMinus reg1 reg2 -> prPrec i 1 (concatD [prt 1 reg1, doc (showString "-"), prt 2 reg2])
      BNFC.Abs.RSeq reg1 reg2 -> prPrec i 2 (concatD [prt 2 reg1, prt 3 reg2])
      BNFC.Abs.RStar reg -> prPrec i 3 (concatD [prt 3 reg, doc (showString "*")])
      BNFC.Abs.RPlus reg -> prPrec i 3 (concatD [prt 3 reg, doc (showString "+")])
      BNFC.Abs.ROpt reg -> prPrec i 3 (concatD [prt 3 reg, doc (showString "?")])
      BNFC.Abs.REps -> prPrec i 3 (concatD [doc (showString "eps")])
      BNFC.Abs.RChar c -> prPrec i 3 (concatD [prt 0 c])
      BNFC.Abs.RAlts str -> prPrec i 3 (concatD [doc (showString "["), printString str, doc (showString "]")])
      BNFC.Abs.RSeqs str -> prPrec i 3 (concatD [doc (showString "{"), printString str, doc (showString "}")])
      BNFC.Abs.RDigit -> prPrec i 3 (concatD [doc (showString "digit")])
      BNFC.Abs.RLetter -> prPrec i 3 (concatD [doc (showString "letter")])
      BNFC.Abs.RUpper -> prPrec i 3 (concatD [doc (showString "upper")])
      BNFC.Abs.RLower -> prPrec i 3 (concatD [doc (showString "lower")])
      BNFC.Abs.RAny -> prPrec i 3 (concatD [doc (showString "char")])
  