Files
gf-core/src/GF/Canon/GFCC/PrintGFCC.hs
2006-09-13 16:49:23 +00:00

183 lines
6.0 KiB
Haskell

{-# OPTIONS -fno-warn-incomplete-patterns #-}
module GF.Canon.GFCC.PrintGFCC where
-- pretty-printer generated by the BNF converter
import GF.Canon.GFCC.AbsGFCC
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 CId where
prt _ (CId i) = doc (showString i)
prtList es = case es of
[] -> (concatD [])
x:xs -> (concatD [prt 0 x , prt 0 xs])
instance Print Grammar where
prt i e = case e of
Grm header abstract concretes -> prPrec i 0 (concatD [prt 0 header , doc (showString ";") , prt 0 abstract , doc (showString ";") , prt 0 concretes , doc (showString ";")])
instance Print Header where
prt i e = case e of
Hdr cid cids -> prPrec i 0 (concatD [doc (showString "grammar") , prt 0 cid , doc (showString "(") , prt 0 cids , doc (showString ")")])
instance Print Abstract where
prt i e = case e of
Abs absdefs -> prPrec i 0 (concatD [doc (showString "abstract") , doc (showString "{") , prt 0 absdefs , doc (showString "}") , doc (showString ";")])
instance Print Concrete where
prt i e = case e of
Cnc cid cncdefs -> prPrec i 0 (concatD [doc (showString "concrete") , prt 0 cid , doc (showString "{") , prt 0 cncdefs , doc (showString "}")])
prtList es = case es of
[] -> (concatD [])
x:xs -> (concatD [prt 0 x , doc (showString ";") , prt 0 xs])
instance Print AbsDef where
prt i e = case e of
Fun cid type' exp -> prPrec i 0 (concatD [prt 0 cid , doc (showString ":") , prt 0 type' , doc (showString "=") , prt 0 exp])
prtList es = case es of
[] -> (concatD [])
x:xs -> (concatD [prt 0 x , doc (showString ";") , prt 0 xs])
instance Print CncDef where
prt i e = case e of
Lin cid term -> prPrec i 0 (concatD [prt 0 cid , doc (showString "=") , prt 0 term])
prtList es = case es of
[] -> (concatD [])
x:xs -> (concatD [prt 0 x , doc (showString ";") , prt 0 xs])
instance Print Type where
prt i e = case e of
Typ cids cid -> prPrec i 0 (concatD [prt 0 cids , doc (showString "->") , prt 0 cid])
instance Print Exp where
prt i e = case e of
Tr atom exps -> prPrec i 0 (concatD [doc (showString "(") , prt 0 atom , prt 0 exps , doc (showString ")")])
prtList es = case es of
[] -> (concatD [])
x:xs -> (concatD [prt 0 x , prt 0 xs])
instance Print Atom where
prt i e = case e of
AC cid -> prPrec i 0 (concatD [prt 0 cid])
AS str -> prPrec i 0 (concatD [prt 0 str])
AI n -> prPrec i 0 (concatD [prt 0 n])
instance Print Term where
prt i e = case e of
R terms -> prPrec i 0 (concatD [doc (showString "[") , prt 0 terms , doc (showString "]")])
P term0 term -> prPrec i 0 (concatD [prt 0 term0 , doc (showString "[") , prt 0 term , doc (showString "]")])
S terms -> prPrec i 0 (concatD [doc (showString "(") , prt 0 terms , doc (showString ")")])
K tokn -> prPrec i 0 (concatD [prt 0 tokn])
V n -> prPrec i 0 (concatD [doc (showString "$") , prt 0 n])
C n -> prPrec i 0 (concatD [prt 0 n])
F cid -> prPrec i 0 (concatD [prt 0 cid])
L cid -> prPrec i 0 (concatD [doc (showString "$") , prt 0 cid])
A cid term -> prPrec i 0 (concatD [doc (showString "(") , prt 0 cid , doc (showString "->") , prt 0 term , doc (showString ")")])
FV terms -> prPrec i 0 (concatD [doc (showString "[|") , prt 0 terms , doc (showString "|]")])
W str term -> prPrec i 0 (concatD [doc (showString "(") , prt 0 str , doc (showString "+") , prt 0 term , doc (showString ")")])
prtList es = case es of
[] -> (concatD [])
[x] -> (concatD [prt 0 x])
x:xs -> (concatD [prt 0 x , doc (showString ",") , prt 0 xs])
instance Print Tokn where
prt i e = case e of
KS str -> prPrec i 0 (concatD [prt 0 str])
KP strs variants -> prPrec i 0 (concatD [doc (showString "[") , doc (showString "pre") , prt 0 strs , doc (showString "[") , prt 0 variants , doc (showString "]") , doc (showString "]")])
instance Print Variant where
prt i e = case e of
Var strs0 strs -> prPrec i 0 (concatD [prt 0 strs0 , doc (showString "/") , prt 0 strs])
prtList es = case es of
[] -> (concatD [])
[x] -> (concatD [prt 0 x])
x:xs -> (concatD [prt 0 x , doc (showString ",") , prt 0 xs])