1 files changed, 152 insertions, 0 deletions
diff --git a/src/Transfer/Core/Print.hs b/src/Transfer/Core/Print.hs
new file mode 100644
index 000000000..8f46f9e5e
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+++ b/src/Transfer/Core/Print.hs
@@ -0,0 +1,152 @@
+{-# OPTIONS_GHC -fglasgow-exts #-}
+module Transfer.Core.Print where
+
+-- pretty-printer generated by the BNF converter
+
+import Transfer.Core.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 decls -> prPrec _i 0 (concatD [prt 0 decls])
+    DataDecl cident exp consdecls -> prPrec _i 0 (concatD [doc (showString "data") , prt 0 cident , doc (showString ":") , prt 0 exp , doc (showString "where") , doc (showString "{") , prt 0 consdecls , doc (showString "}")])
+    TypeDecl cident exp -> prPrec _i 0 (concatD [prt 0 cident , doc (showString ":") , prt 0 exp])
+    ValueDecl cident exp -> prPrec _i 0 (concatD [prt 0 cident , doc (showString "=") , prt 0 exp])
+    ConsDecl cident exp -> prPrec _i 0 (concatD [prt 0 cident , doc (showString ":") , prt 0 exp])
+    PCons cident patterns -> prPrec _i 0 (concatD [doc (showString "(") , prt 0 cident , prt 0 patterns , doc (showString ")")])
+    PVar patternvariable -> prPrec _i 0 (concatD [prt 0 patternvariable])
+    PRec fieldpatterns -> prPrec _i 0 (concatD [doc (showString "{") , prt 0 fieldpatterns , doc (showString "}")])
+    PType  -> prPrec _i 0 (concatD [doc (showString "Type")])
+    PStr str -> prPrec _i 0 (concatD [prt 0 str])
+    PInt n -> prPrec _i 0 (concatD [prt 0 n])
+    FieldPattern cident pattern -> prPrec _i 0 (concatD [prt 0 cident , doc (showString "=") , prt 0 pattern])
+    PVVar cident -> prPrec _i 0 (concatD [prt 0 cident])
+    PVWild  -> prPrec _i 0 (concatD [doc (showString "_")])
+    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 "}")])
+    EAbs patternvariable exp -> prPrec _i 2 (concatD [doc (showString "\\") , prt 0 patternvariable , doc (showString "->") , prt 0 exp])
+    EPi patternvariable exp0 exp1 -> prPrec _i 2 (concatD [doc (showString "(") , prt 0 patternvariable , doc (showString ":") , prt 0 exp0 , doc (showString ")") , doc (showString "->") , prt 0 exp1])
+    EApp exp0 exp1 -> prPrec _i 3 (concatD [prt 3 exp0 , prt 4 exp1])
+    EProj exp cident -> prPrec _i 4 (concatD [prt 4 exp , doc (showString ".") , prt 0 cident])
+    EEmptyRec  -> prPrec _i 5 (concatD [doc (showString "{") , doc (showString "}")])
+    ERecType fieldtypes -> prPrec _i 5 (concatD [doc (showString "{") , prt 0 fieldtypes , doc (showString "}")])
+    ERec fieldvalues -> prPrec _i 5 (concatD [doc (showString "{") , prt 0 fieldvalues , doc (showString "}")])
+    EVar cident -> prPrec _i 5 (concatD [prt 0 cident])
+    EType  -> prPrec _i 5 (concatD [doc (showString "Type")])
+    EStr str -> prPrec _i 5 (concatD [prt 0 str])
+    EInt n -> prPrec _i 5 (concatD [prt 0 n])
+    LetDef cident exp0 exp1 -> prPrec _i 0 (concatD [prt 0 cident , 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])
+    FieldType cident exp -> prPrec _i 0 (concatD [prt 0 cident , doc (showString ":") , prt 0 exp])
+    FieldValue cident exp -> prPrec _i 0 (concatD [prt 0 cident , doc (showString "=") , prt 0 exp])
+    CIdent str -> prPrec _i 0 (doc (showString str))
+
+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 0 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])