implementation module parse
import StdString
+import StdTuple
+import StdList
+from StdFunc import const, o
+import Data.Either
+import Data.Functor
+import Data.Maybe
+import Control.Monad
+import Control.Applicative
+import Data.Func
+from Data.List import intercalate, replicate, instance Functor []
+from Text import class Text(concat), instance Text String
+import GenPrint
+import yard
import lex
-parse :: LexerOutput -> ParserOutput
-parse (Left e) = Left ("Lexer error: " +++ e)
-parse (Right r) = Left "Parser not yet implemented"
+parser :: LexerOutput -> ParserOutput
+parser (Left e) = Left e
+parser (Right r) = fst $ runParser parseProgram r
+
+parseProgram :: Parser Token AST
+parseProgram = liftM2 AST (many parseVarDecl) (some parseFunDecl)
+
+parseFunDecl :: Parser Token FunDecl
+parseFunDecl = liftM5 FunDecl
+ (parseIdent <* satTok BraceOpenToken)
+ (parseSepList CommaToken parseIdent <* satTok BraceCloseToken)
+ (optional parseFunType <* satTok CBraceOpenToken)
+ (many parseVarDecl)
+ (many parseStmt <* satTok CBraceCloseToken)
+
+parseStmt :: Parser Token Stmt
+parseStmt = parseIfStmt <|> parseWhileStmt <|>
+ parseSColon parseAssStmt <|> parseSColon parseReturnStmt <|>
+ (liftM FunStmt (parseSColon parseFunCall))
+ where
+ parseSColon :: (Parser Token a) -> Parser Token a
+ parseSColon p = p <* satTok SColonToken
+
+ parseReturnStmt :: Parser Token Stmt
+ parseReturnStmt =
+ satTok ReturnToken *> liftM ReturnStmt (optional parseExpr)
+
+ parseAssStmt :: Parser Token Stmt
+ parseAssStmt =
+ liftM2 AssStmt (parseVarDef <* satTok AssignmentToken) parseExpr
+
+ parseIfStmt :: Parser Token Stmt
+ parseIfStmt = liftM3 IfStmt
+ (satTok IfToken *> parseBBraces parseExpr)
+ (parseBlock <|> parseOneLine)
+ (liftM (fromMaybe [])
+ (optional (satTok ElseToken *> (parseBlock<|> parseOneLine))))
+
+
+ parseWhileStmt :: Parser Token Stmt
+ parseWhileStmt = satTok WhileToken *>
+ liftM2 WhileStmt (parseBBraces parseExpr) parseBlock
+
+ parseBlock :: Parser Token [Stmt]
+ parseBlock = parseBCBraces (many parseStmt)
+
+ parseOneLine :: Parser Token [Stmt]
+ //first pure makes singleton list from the statement
+ parseOneLine = liftM pure parseStmt
+
+parseFunType :: Parser Token FunType
+parseFunType = satTok DoubleColonToken *>
+ (parseInOutType <|> (liftM (FunType []) parseVoidOrType))
+ where
+ parseInOutType :: Parser Token FunType
+ parseInOutType = liftM2 FunType
+ (some parseType <* satTok ArrowToken) parseVoidOrType
+
+ parseVoidOrType :: Parser Token (Maybe Type)
+ parseVoidOrType = (satTok VoidToken *> pure Nothing) <|>
+ (liftM Just parseType) <|> pure Nothing
+
+parseVarDecl :: Parser Token VarDecl
+parseVarDecl = liftM3 VarDecl
+ (parseType <|> trans1 VarToken VarType )
+ (parseIdent <* satTok AssignmentToken)
+ (parseExpr <* satTok SColonToken)
+
+parseType :: Parser Token Type
+parseType =
+ trans1 IntTypeToken IntType <|>
+ trans1 CharTypeToken CharType <|>
+ trans1 BoolTypeToken BoolType <|>
+ (liftM ListType (parseBSqBraces parseType)) <|>
+ (liftM TupleType (parseTuple parseType)) <|>
+ (liftM IdType parseIdent)
+
+parseExpr :: Parser Token Expr
+parseExpr = //Operators in order of binding strength
+ parseOpR (trans1 ColonToken BiCons) $
+ parseOpR (trans1 PipesToken BiOr) $
+ parseOpR (trans1 AmpersandsToken BiAnd) $
+ parseOpR (trans1 EqualsToken BiEquals <|>
+ trans1 LesserToken BiLesser <|>
+ trans1 BiggerToken BiGreater <|>
+ trans1 LesserEqToken BiLesserEq <|>
+ trans1 GreaterEqToken BiGreaterEq <|>
+ trans1 NotEqualToken BiUnEqual) $
+ parseOpL (trans1 PlusToken BiPlus <|>
+ trans1 DashToken BiMinus) $
+ parseOpL (trans1 StarToken BiTimes <|>
+ trans1 SlashToken BiDivide <|>
+ trans1 PercentToken BiMod) $ parseBasicExpr
+ where
+ parseOpR :: (Parser Token Op2) (Parser Token Expr) -> Parser Token Expr
+ parseOpR ops prev = prev >>= \e1->optional (
+ ops >>= \op->parseOpR ops prev >>= \e->pure (op, e)
+ ) >>= \moe->pure $ maybe e1 (\(op,e2)->Op2Expr e1 op e2) moe
+
+ parseOpL :: (Parser Token Op2) (Parser Token Expr) -> Parser Token Expr
+ parseOpL ops prev = prev >>= \e1->many (
+ ops >>= \op->prev >>= \e->pure (op, e)
+ ) >>= \moe->foldM (\e->(\(op,e2)->pure $ Op2Expr e op e2)) e1 moe
+
+ parseBasicExpr :: Parser Token Expr
+ parseBasicExpr =
+ (liftM TupleExpr (parseTuple parseExpr)) <|>
+ (liftM FunExpr parseFunCall) <|>
+ parseBBraces parseExpr <|>
+ trans1 EmptyListToken EmptyListExpr <|>
+ trans1 TrueToken (BoolExpr True) <|>
+ trans1 FalseToken (BoolExpr False) <|>
+ trans2 (NumberToken zero) (\(NumberToken i)->IntExpr i) <|>
+ trans2 (CharToken zero) (\(CharToken c)->CharExpr c) <|>
+ (liftM2 Op1Expr parseOp1 parseExpr) <|>
+ (liftM VarExpr parseVarDef)
+
+parseFunCall :: Parser Token FunCall
+parseFunCall = liftM2 FunCall
+ parseIdent (parseBBraces $ parseSepList CommaToken parseExpr)
+
+parseVarDef :: Parser Token VarDef
+parseVarDef = liftM2 VarDef
+ parseIdent
+ (many (satTok DotToken *> (
+ (parseIdent >>= (\i.if (i == "hd") (pure FieldHd) empty)) <|>
+ (parseIdent >>= \i.if (i == "tl") (pure FieldTl) empty) <|>
+ (parseIdent >>= \i.if (i == "fst") (pure FieldFst) empty) <|>
+ (parseIdent >>= \i.if (i == "snd") (pure FieldSnd) empty))))
+
+parseOp1 :: Parser Token Op1
+parseOp1 = trans1 DashToken UnMinus <|> trans1 ExclamationToken UnNegation
+
+parseBBraces :: (Parser Token a) -> Parser Token a
+parseBBraces p = satTok BraceOpenToken *> p <* satTok BraceCloseToken
+
+parseBCBraces :: (Parser Token a) -> Parser Token a
+parseBCBraces p = satTok CBraceOpenToken *> p <* satTok CBraceCloseToken
+
+parseBSqBraces :: (Parser Token a) -> Parser Token a
+parseBSqBraces p = satTok SquareOpenToken *> p <* satTok SquareCloseToken
+
+parseTuple :: (Parser Token a) -> Parser Token (a, a)
+parseTuple p = satTok BraceOpenToken *>
+ (liftM2 (\a->(\b->(a,b))) (p <* satTok CommaToken) p)
+ <* satTok BraceCloseToken
+
+trans2 :: TokenValue (TokenValue -> a) -> Parser Token a
+trans2 t f = liftM (\{token}->f token) $ satTok t
+
+trans1 :: TokenValue a -> Parser Token a
+trans1 t r = trans2 t $ const r
+
+derive gPrint TokenValue
+derive gEq TokenValue
+satTok :: TokenValue -> Parser Token Token
+satTok t = top >>= \tok=:{line,column,token} -> if (eq t token)
+ (return tok) (fail <?> PositionalError line column ("ParseError: Unexpected token: " +++ printToString token))
+ where
+ eq (IdentToken _) (IdentToken _) = True
+ eq (NumberToken _) (NumberToken _) = True
+ eq (CharToken _) (CharToken _) = True
+ eq x y = gEq {|*|} x y
+
+parseSepList :: TokenValue (Parser Token a) -> Parser Token [a]
+parseSepList sep p =
+ (liftM2 (\es->(\e->reverse [e:es])) (some (p <* satTok sep)) p) <|>
+ (liftM pure p) <|> pure empty
+
+parseIdent :: Parser Token String
+parseIdent = trans2 (IdentToken "") (\(IdentToken e).toString e)
+
+instance toString AST where
+ toString (AST v f) = concat (
+ ["\n":printersperse "\n" v] ++
+ ["\n":printersperse "\n" f])
+
+class print a :: a -> [String]
+
+printersperse :: String [a] -> [String] | print a
+printersperse i j = intercalate [i] (map print j)
+
+instance print FunDecl where
+ print (FunDecl i as t vs ss) =
+ ["\n", i, " (":printersperse "," as] ++
+ [")"] ++ maybe [] (\tt->[" :: ":print tt]) t ++
+ ["{\n\t":printersperse "\n\t" vs] ++
+ ["\n":printStatements ss 1] ++ ["}\n"]
+
+printStatements :: [Stmt] Int -> [String]
+printStatements [] i = []
+printStatements [s:ss] i = (case s of
+ (IfStmt b thens elses) = indent i ["if (":print b] ++ [")"] ++
+ printCodeBlock thens i ++
+ indent i ["else ":printCodeBlock elses i] ++ ["\n"]
+ (WhileStmt b dos) = indent i ["while (":print b] ++
+ [")":printCodeBlock dos i]
+ (AssStmt vardef val) =
+ indent i $ print vardef ++ ["=":print val] ++ [";\n"]
+ (FunStmt fc) = indent i $ print fc ++ [";\n"]
+ (ReturnStmt me) = indent i ["return ":maybe [""] print me] ++ [";\n"]
+ ) ++ printStatements ss i
+ where
+ printCodeBlock :: [Stmt] Int -> [String]
+ printCodeBlock [] _ = ["{}\n"]
+ printCodeBlock [x] i = ["\n":printStatements [x] (i+1)]
+ printCodeBlock x i =
+ ["{\n":printStatements x (i+1)] ++ indent i ["}\n"]
+
+ indent :: Int [String] -> [String]
+ indent i rest = replicate i "\t" ++ rest
+
+instance print FunType where
+ print (FunType at rt) = printersperse " " at ++
+ [if (isEmpty at) "" "->":maybe ["Void"] print rt]
+
+instance print VarDecl where
+ print (VarDecl t i e) = print t ++ [" ":i:"=":print e] ++ [";"]
+
+instance print Type where
+ print (TupleType (t1, t2)) = ["(":print t1] ++ [",":print t2] ++ [")"]
+ print (ListType t) = ["[":print t] ++ ["]"]
+ print (IdType s) = print s
+ print IntType = print "Int"
+ print BoolType = print "Bool"
+ print CharType = print "Char"
+ print VarType = print "var"
+
+instance print String where
+ print s = [s]
+
+instance print FieldSelector where
+ print FieldHd = print "hd"
+ print FieldTl = print "tl"
+ print FieldSnd = print "snd"
+ print FieldFst = print "fst"
+
+instance print VarDef where
+ print (VarDef i fs) = printersperse "." [i:flatten $ map print fs]
+
+instance print FunCall where
+ print (FunCall i args) = [i,"(":printersperse "," args] ++ [")"]
+
+instance print Expr where
+ print (VarExpr vd) = print vd
+ print (Op2Expr e1 o e2) = ["(":print e1] ++ [" ",case o of
+ BiPlus = "+"; BiMinus = "-"; BiTimes = "*"; BiDivide = "/"
+ BiMod = "%"; BiEquals = "="; BiLesser = "<"; BiGreater = ">"
+ BiLesserEq = "<="; BiGreaterEq = ">="; BiUnEqual = "!=";
+ BiAnd = "&&"; BiOr = "||"; BiCons = ":"
+ ," ":print e2] ++ [")"]
+ print (Op1Expr o e) = ["(",case o of
+ UnNegation = "!"; UnMinus = "-"
+ :print e] ++ [")"]
+ print (IntExpr i) = [toString i]
+ print (CharExpr c) = ["\'", case c of
+ '\b' = "\\b"; '\f' = "\\f"; '\n' = "\\n"
+ '\r' = "\\r"; '\t' = "\\t"; '\v' = "\\v"
+ c = if (c == toChar 7) "\\a" (toString c)
+ ,"\'"]
+ print (BoolExpr b) = [toString b]
+ print (FunExpr fc) = print fc
+ print EmptyListExpr = ["[]"]
+ print (TupleExpr (e1, e2)) = ["(":print e1] ++ [",":print e2] ++ [")"]