1
0
forked from GitHub/gf-core
Files
gf-core/src/Transfer/Syntax/Print.hs

179 lines
8.5 KiB
Haskell

{-# OPTIONS_GHC -fglasgow-exts #-}
module Transfer.Syntax.Print where
-- pretty-printer generated by the BNF converter
import Transfer.Syntax.Abs
import Data.Char
import Data.List (intersperse)
-- 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
unwordsD :: [Doc] -> Doc
unwordsD = concatD . intersperse (doc (showChar ' '))
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 Print Char where
prt _ s = doc (showChar '\'' . mkEsc '\'' s . showChar '\'')
instance Print String where
prt _ 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 (Tree c) where
prt _i e = case e of
Module imports decls -> prPrec _i 0 (concatD [prt 0 imports , prt 0 decls])
Import i -> prPrec _i 0 (concatD [doc (showString "import") , prt 0 i])
DataDecl i exp consdecls -> prPrec _i 0 (concatD [doc (showString "data") , prt 0 i , doc (showString ":") , prt 0 exp , doc (showString "where") , doc (showString "{") , prt 0 consdecls , doc (showString "}")])
TypeDecl i exp -> prPrec _i 0 (concatD [prt 0 i , doc (showString ":") , prt 0 exp])
ValueDecl i patterns exp -> prPrec _i 0 (concatD [prt 0 i , prt 0 patterns , doc (showString "=") , prt 0 exp])
DeriveDecl i0 i1 -> prPrec _i 0 (concatD [doc (showString "derive") , prt 0 i0 , prt 0 i1])
ConsDecl i exp -> prPrec _i 0 (concatD [prt 0 i , doc (showString ":") , prt 0 exp])
PConsTop i pattern patterns -> prPrec _i 0 (concatD [prt 0 i , prt 1 pattern , prt 0 patterns])
PCons i patterns -> prPrec _i 1 (concatD [doc (showString "(") , prt 0 i , prt 0 patterns , doc (showString ")")])
PRec fieldpatterns -> prPrec _i 1 (concatD [doc (showString "{") , prt 0 fieldpatterns , doc (showString "}")])
PType -> prPrec _i 1 (concatD [doc (showString "Type")])
PStr str -> prPrec _i 1 (concatD [prt 0 str])
PInt n -> prPrec _i 1 (concatD [prt 0 n])
PVar i -> prPrec _i 1 (concatD [prt 0 i])
PWild -> prPrec _i 1 (concatD [doc (showString "_")])
FieldPattern i pattern -> prPrec _i 0 (concatD [prt 0 i , doc (showString "=") , prt 0 pattern])
ELet letdefs exp -> prPrec _i 0 (concatD [doc (showString "let") , doc (showString "{") , prt 0 letdefs , doc (showString "}") , doc (showString "in") , prt 0 exp])
ECase exp cases -> prPrec _i 0 (concatD [doc (showString "case") , prt 0 exp , doc (showString "of") , doc (showString "{") , prt 0 cases , doc (showString "}")])
EIf exp0 exp1 exp2 -> prPrec _i 0 (concatD [doc (showString "if") , prt 0 exp0 , doc (showString "then") , prt 0 exp1 , doc (showString "else") , prt 0 exp2])
EAbs varorwild exp -> prPrec _i 2 (concatD [doc (showString "\\") , prt 0 varorwild , doc (showString "->") , prt 0 exp])
EPi varorwild exp0 exp1 -> prPrec _i 2 (concatD [doc (showString "(") , prt 0 varorwild , doc (showString ":") , prt 0 exp0 , doc (showString ")") , doc (showString "->") , prt 0 exp1])
EPiNoVar exp0 exp1 -> prPrec _i 2 (concatD [prt 3 exp0 , doc (showString "->") , prt 0 exp1])
EOr exp0 exp1 -> prPrec _i 3 (concatD [prt 4 exp0 , doc (showString "||") , prt 3 exp1])
EAnd exp0 exp1 -> prPrec _i 4 (concatD [prt 5 exp0 , doc (showString "&&") , prt 4 exp1])
EEq exp0 exp1 -> prPrec _i 5 (concatD [prt 6 exp0 , doc (showString "==") , prt 6 exp1])
ENe exp0 exp1 -> prPrec _i 5 (concatD [prt 6 exp0 , doc (showString "/=") , prt 6 exp1])
ELt exp0 exp1 -> prPrec _i 5 (concatD [prt 6 exp0 , doc (showString "<") , prt 6 exp1])
ELe exp0 exp1 -> prPrec _i 5 (concatD [prt 6 exp0 , doc (showString "<=") , prt 6 exp1])
EGt exp0 exp1 -> prPrec _i 5 (concatD [prt 6 exp0 , doc (showString ">") , prt 6 exp1])
EGe exp0 exp1 -> prPrec _i 5 (concatD [prt 6 exp0 , doc (showString ">=") , prt 6 exp1])
EAdd exp0 exp1 -> prPrec _i 6 (concatD [prt 6 exp0 , doc (showString "+") , prt 7 exp1])
ESub exp0 exp1 -> prPrec _i 6 (concatD [prt 6 exp0 , doc (showString "-") , prt 7 exp1])
EMul exp0 exp1 -> prPrec _i 7 (concatD [prt 7 exp0 , doc (showString "*") , prt 8 exp1])
EDiv exp0 exp1 -> prPrec _i 7 (concatD [prt 7 exp0 , doc (showString "/") , prt 8 exp1])
EMod exp0 exp1 -> prPrec _i 7 (concatD [prt 7 exp0 , doc (showString "%") , prt 8 exp1])
ENeg exp -> prPrec _i 8 (concatD [doc (showString "-") , prt 8 exp])
EApp exp0 exp1 -> prPrec _i 9 (concatD [prt 9 exp0 , prt 10 exp1])
EProj exp i -> prPrec _i 10 (concatD [prt 10 exp , doc (showString ".") , prt 0 i])
EEmptyRec -> prPrec _i 11 (concatD [doc (showString "{") , doc (showString "}")])
ERecType fieldtypes -> prPrec _i 11 (concatD [doc (showString "{") , prt 0 fieldtypes , doc (showString "}")])
ERec fieldvalues -> prPrec _i 11 (concatD [doc (showString "{") , prt 0 fieldvalues , doc (showString "}")])
EVar i -> prPrec _i 11 (concatD [prt 0 i])
EType -> prPrec _i 11 (concatD [doc (showString "Type")])
EStr str -> prPrec _i 11 (concatD [prt 0 str])
EInt n -> prPrec _i 11 (concatD [prt 0 n])
EMeta -> prPrec _i 11 (concatD [doc (showString "?")])
LetDef i exp0 exp1 -> prPrec _i 0 (concatD [prt 0 i , doc (showString ":") , prt 0 exp0 , doc (showString "=") , prt 0 exp1])
Case pattern exp -> prPrec _i 0 (concatD [prt 0 pattern , doc (showString "->") , prt 0 exp])
VVar i -> prPrec _i 0 (concatD [prt 0 i])
VWild -> prPrec _i 0 (concatD [doc (showString "_")])
FieldType i exp -> prPrec _i 0 (concatD [prt 0 i , doc (showString ":") , prt 0 exp])
FieldValue i exp -> prPrec _i 0 (concatD [prt 0 i , doc (showString "=") , prt 0 exp])
Ident str -> prPrec _i 0 (doc (showString str))
instance Print [Import] where
prt _ es = case es of
[] -> (concatD [])
[x] -> (concatD [prt 0 x])
x:xs -> (concatD [prt 0 x , doc (showString ";") , prt 0 xs])
instance Print [Decl] where
prt _ es = case es of
[] -> (concatD [])
[x] -> (concatD [prt 0 x])
x:xs -> (concatD [prt 0 x , doc (showString ";") , prt 0 xs])
instance Print [ConsDecl] where
prt _ es = case es of
[] -> (concatD [])
[x] -> (concatD [prt 0 x])
x:xs -> (concatD [prt 0 x , doc (showString ";") , prt 0 xs])
instance Print [Pattern] where
prt _ es = case es of
[] -> (concatD [])
x:xs -> (concatD [prt 1 x , prt 0 xs])
instance Print [FieldPattern] where
prt _ es = case es of
[] -> (concatD [])
[x] -> (concatD [prt 0 x])
x:xs -> (concatD [prt 0 x , doc (showString ";") , prt 0 xs])
instance Print [LetDef] where
prt _ es = case es of
[] -> (concatD [])
[x] -> (concatD [prt 0 x])
x:xs -> (concatD [prt 0 x , doc (showString ";") , prt 0 xs])
instance Print [Case] where
prt _ es = case es of
[] -> (concatD [])
[x] -> (concatD [prt 0 x])
x:xs -> (concatD [prt 0 x , doc (showString ";") , prt 0 xs])
instance Print [FieldType] where
prt _ es = case es of
[x] -> (concatD [prt 0 x])
x:xs -> (concatD [prt 0 x , doc (showString ";") , prt 0 xs])
instance Print [FieldValue] where
prt _ es = case es of
[x] -> (concatD [prt 0 x])
x:xs -> (concatD [prt 0 x , doc (showString ";") , prt 0 xs])