Print.hs

{-# OPTIONS -fno-warn-incomplete-patterns #-}
module Language.Pec.Print where

-- pretty-printer generated by the BNF converter

import Language.Pec.Abs
import Data.Char


-- 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 (map ($ "") $ d []) "" where
  rend i ss = case ss of
    "["      :ts -> showChar '[' . rend i ts
    "("      :ts -> showChar '(' . rend i ts
    "{"      :ts -> showChar '{' . new (i+1) . rend (i+1) ts
    "}" : ";":ts -> new (i-1) . space "}" . showChar ';' . new (i-1) . rend (i-1) ts
    "}"      :ts -> new (i-1) . showChar '}' . new (i-1) . rend (i-1) ts
    ";"      :ts -> showChar ';' . new i . rend i ts
    t  : "," :ts -> showString t . space "," . rend i ts
    t  : ")" :ts -> showString t . showChar ')' . rend i ts
    t  : "]" :ts -> showString t . showChar ']' . rend i ts
    t        :ts -> space t . rend i ts
    _            -> id
  new i   = showChar '\n' . replicateS (2*i) (showChar ' ') . dropWhile isSpace
  space t = showString t . (\s -> if null s then "" else (' ':s))

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
  prtList :: [a] -> Doc
  prtList = concatD . map (prt 0)

instance Print a => Print [a] where
  prt _ = prtList

instance Print Char where
  prt _ s = doc (showChar '\'' . mkEsc '\'' s . showChar '\'')
  prtList s = doc (showChar '"' . concatS (map (mkEsc '"') s) . showChar '"')

mkEsc :: Char -> Char -> ShowS
mkEsc q s = case s of
  _ | s == q -> showChar '\\' . showChar s
  '\\'-> showString "\\\\"
  '\n' -> showString "\\n"
  '\t' -> showString "\\t"
  _ -> 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 Frac where
  prt _ (Frac i) = doc (showString ( i))


instance Print Uident where
  prt _ (Uident i) = doc (showString ( i))


instance Print Lident where
  prt _ (Lident i) = doc (showString ( i))


instance Print USym where
  prt _ (USym i) = doc (showString ( i))


instance Print Number where
  prt _ (Number i) = doc (showString ( i))


instance Print Count where
  prt _ (Count i) = doc (showString ( i))



instance Print Module where
  prt i e = case e of
   Module modid exportdecl topdecls -> prPrec i 0 (concatD [doc (showString "module") , prt 0 modid , doc (showString "exports") , prt 0 exportdecl , doc (showString "where") , doc (showString "{") , prt 0 topdecls , doc (showString "}")])


instance Print ExportDecl where
  prt i e = case e of
   ExpAllD  -> prPrec i 0 (concatD [doc (showString "all")])
   ExpListD exports -> prPrec i 0 (concatD [doc (showString "(") , prt 0 exports , doc (showString ")")])


instance Print Export where
  prt i e = case e of
   TypeEx con spec -> prPrec i 0 (concatD [prt 0 con , prt 0 spec])
   VarEx var -> prPrec i 0 (concatD [prt 0 var])

  prtList es = case es of
   [] -> (concatD [])
   [x] -> (concatD [prt 0 x])
   x:xs -> (concatD [prt 0 x , doc (showString ",") , prt 0 xs])

instance Print Spec where
  prt i e = case e of
   Neither  -> prPrec i 0 (concatD [])
   Decon  -> prPrec i 0 (concatD [doc (showString "(") , doc (showString ".") , doc (showString ")")])
   Both  -> prPrec i 0 (concatD [doc (showString "(") , doc (showString "..") , doc (showString ")")])


instance Print TopDecl where
  prt i e = case e of
   ImportD modid asspec -> prPrec i 0 (concatD [doc (showString "import") , prt 0 modid , prt 0 asspec])
   ExternD extnm var type' -> prPrec i 0 (concatD [doc (showString "extern") , prt 0 extnm , prt 0 var , doc (showString "::") , prt 0 type'])
   TypeD con tyvars tydecl -> prPrec i 0 (concatD [doc (showString "type") , prt 0 con , prt 0 tyvars , doc (showString "=") , prt 0 tydecl])
   AscribeD var type' -> prPrec i 0 (concatD [prt 0 var , doc (showString "::") , prt 0 type'])
   VarD var exp -> prPrec i 0 (concatD [prt 0 var , doc (showString "=") , prt 0 exp])
   ProcD var exps exp -> prPrec i 0 (concatD [prt 0 var , prt 0 exps , doc (showString "=") , prt 0 exp])

  prtList es = case es of
   [] -> (concatD [])
   [x] -> (concatD [prt 0 x])
   x:xs -> (concatD [prt 0 x , doc (showString ";") , prt 0 xs])

instance Print AsSpec where
  prt i e = case e of
   AsAS con -> prPrec i 0 (concatD [doc (showString "as") , prt 0 con])
   EmptyAS  -> prPrec i 0 (concatD [])


instance Print ExtNm where
  prt i e = case e of
   SomeNm str -> prPrec i 0 (concatD [prt 0 str])
   NoneNm  -> prPrec i 0 (concatD [])


instance Print Exp where
  prt i e = case e of
   BlockE exps -> prPrec i 0 (concatD [doc (showString "do") , doc (showString "{") , prt 5 exps , doc (showString "}")])
   LetS exp0 exp -> prPrec i 5 (concatD [prt 4 exp0 , doc (showString "=") , prt 0 exp])
   LetE exp0 exp1 exp -> prPrec i 5 (concatD [doc (showString "let") , prt 4 exp0 , doc (showString "=") , prt 0 exp1 , doc (showString "in") , prt 0 exp])
   StoreE exp0 exp -> prPrec i 5 (concatD [prt 4 exp0 , doc (showString "<-") , prt 0 exp])
   CaseE exp casealts -> prPrec i 5 (concatD [doc (showString "case") , prt 0 exp , doc (showString "of") , doc (showString "{") , prt 0 casealts , doc (showString "}")])
   BranchE branchalts -> prPrec i 5 (concatD [doc (showString "branch") , doc (showString "of") , doc (showString "{") , prt 0 branchalts , doc (showString "}")])
   BinOpE exp0 usym exp -> prPrec i 4 (concatD [prt 3 exp0 , prt 0 usym , prt 3 exp])
   AppE exp0 exp -> prPrec i 3 (concatD [prt 3 exp0 , prt 2 exp])
   UnOpE unop exp -> prPrec i 2 (concatD [prt 0 unop , prt 1 exp])
   IdxE exp0 exp -> prPrec i 1 (concatD [prt 1 exp0 , doc (showString "[") , prt 0 exp , doc (showString "]")])
   FldE exp field -> prPrec i 1 (concatD [prt 1 exp , doc (showString ".") , prt 0 field])
   ArrayE exps -> prPrec i 0 (concatD [doc (showString "Array") , doc (showString "[") , prt 0 exps , doc (showString "]")])
   RecordE fieldds -> prPrec i 0 (concatD [doc (showString "{") , prt 0 fieldds , doc (showString "}")])
   TupleE exps -> prPrec i 0 (concatD [doc (showString "(") , prt 0 exps , doc (showString ")")])
   AscribeE exp type' -> prPrec i 0 (concatD [doc (showString "(") , prt 0 exp , doc (showString "::") , prt 0 type' , doc (showString ")")])
   CountE count -> prPrec i 0 (concatD [prt 0 count])
   VarE var -> prPrec i 0 (concatD [prt 0 var])
   LitE lit -> prPrec i 0 (concatD [prt 0 lit])

  prtList es = case es of
   [] -> (concatD [])
   [x] -> (concatD [prt 0 x])
   [x] -> (concatD [prt 0 x])
   [x] -> (concatD [prt 5 x])
   x:xs -> (concatD [prt 0 x , doc (showString ",") , prt 0 xs])
   x:xs -> (concatD [prt 0 x , prt 0 xs])
   x:xs -> (concatD [prt 5 x , doc (showString ";") , prt 5 xs])

instance Print UnOp where
  prt i e = case e of
   Load  -> prPrec i 0 (concatD [doc (showString "@")])


instance Print CaseAlt where
  prt i e = case e of
   CaseAlt casepat exp -> prPrec i 0 (concatD [prt 0 casepat , doc (showString "->") , prt 0 exp])

  prtList es = case es of
   [x] -> (concatD [prt 0 x])
   x:xs -> (concatD [prt 0 x , doc (showString ";") , prt 0 xs])

instance Print CasePat where
  prt i e = case e of
   ConP con var -> prPrec i 0 (concatD [prt 0 con , prt 0 var])
   LitP lit -> prPrec i 0 (concatD [prt 0 lit])
   VarP var -> prPrec i 0 (concatD [prt 0 var])


instance Print BranchAlt where
  prt i e = case e of
   BranchAlt branchpat exp -> prPrec i 0 (concatD [doc (showString "|") , prt 0 branchpat , doc (showString "->") , prt 0 exp])

  prtList es = case es of
   [x] -> (concatD [prt 0 x])
   x:xs -> (concatD [prt 0 x , doc (showString ";") , prt 0 xs])

instance Print BranchPat where
  prt i e = case e of
   BoolBP exp -> prPrec i 0 (concatD [prt 4 exp])
   DefaultBP  -> prPrec i 0 (concatD [])


instance Print Type where
  prt i e = case e of
   TyFun type'0 type' -> prPrec i 0 (concatD [prt 2 type'0 , doc (showString "->") , prt 0 type'])
   TyArray type'0 type' -> prPrec i 2 (concatD [doc (showString "Array") , prt 1 type'0 , prt 1 type'])
   TyConstr con types -> prPrec i 2 (concatD [prt 0 con , prt 1 types])
   TyTuple types -> prPrec i 0 (concatD [doc (showString "(") , prt 0 types , doc (showString ")")])
   TyCount count -> prPrec i 0 (concatD [prt 0 count])
   TyVarT tyvar -> prPrec i 0 (concatD [prt 0 tyvar])
   TyConstr0 con -> prPrec i 0 (concatD [prt 0 con])

  prtList es = case es of
   [] -> (concatD [])
   [] -> (concatD [])
   [x] -> (concatD [prt 0 x])
   [x] -> (concatD [prt 1 x])
   x:xs -> (concatD [prt 0 x , doc (showString ",") , prt 0 xs])
   x:xs -> (concatD [prt 0 x , prt 0 xs])
   x:xs -> (concatD [prt 1 x , prt 1 xs])

instance Print TyDecl where
  prt i e = case e of
   TyRecord fieldts -> prPrec i 0 (concatD [doc (showString "{") , prt 0 fieldts , doc (showString "}")])
   TyTagged concs -> prPrec i 0 (concatD [doc (showString "|") , prt 0 concs])
   TySyn type' -> prPrec i 0 (concatD [prt 0 type'])


instance Print ConC where
  prt i e = case e of
   ConC con types -> prPrec i 0 (concatD [prt 0 con , prt 0 types])

  prtList es = case es of
   [x] -> (concatD [prt 0 x])
   x:xs -> (concatD [prt 0 x , doc (showString "|") , prt 0 xs])

instance Print FieldT where
  prt i e = case e of
   FieldT field type' -> prPrec i 0 (concatD [prt 0 field , doc (showString "::") , prt 0 type'])

  prtList es = case es of
   [] -> (concatD [])
   [x] -> (concatD [prt 0 x])
   x:xs -> (concatD [prt 0 x , doc (showString ",") , prt 0 xs])

instance Print Lit where
  prt i e = case e of
   CharL c -> prPrec i 0 (concatD [prt 0 c])
   StringL str -> prPrec i 0 (concatD [prt 0 str])
   IntL number -> prPrec i 0 (concatD [prt 0 number])
   FracL frac -> prPrec i 0 (concatD [prt 0 frac])
   EnumL con -> prPrec i 0 (concatD [prt 0 con])


instance Print FieldD where
  prt i e = case e of
   FieldD field exp -> prPrec i 0 (concatD [prt 0 field , doc (showString "=") , prt 0 exp])

  prtList es = case es of
   [x] -> (concatD [prt 0 x])
   x:xs -> (concatD [prt 0 x , doc (showString ",") , prt 0 xs])

instance Print Var where
  prt i e = case e of
   Var lident -> prPrec i 0 (concatD [prt 0 lident])


instance Print Con where
  prt i e = case e of
   Con uident -> prPrec i 0 (concatD [prt 0 uident])


instance Print Modid where
  prt i e = case e of
   Modid uident -> prPrec i 0 (concatD [prt 0 uident])


instance Print Field where
  prt i e = case e of
   Field lident -> prPrec i 0 (concatD [prt 0 lident])


instance Print TyVar where
  prt i e = case e of
   VarTV lident -> prPrec i 0 (concatD [prt 0 lident])
   CntTV lident -> prPrec i 0 (concatD [doc (showString "#") , prt 0 lident])

  prtList es = case es of
   [] -> (concatD [])
   x:xs -> (concatD [prt 0 x , prt 0 xs])