fixed nasty pretty print bug, added selftest to readme

[cc1516.git] / parse.icl

diff --git a/parse.icl b/parse.icl
index dfb0708..34ec15b 100644 (file)
--- a/parse.icl
+++ b/parse.icl
@@ -23,20 +23,21 @@ parser (Left e) = Left e
 parser (Right r) = fst $ runParser parseProgram r
 
 parseProgram :: Parser Token AST
-parseProgram = liftM2 AST (many parseVarDecl) (some parseFunDecl)
+parseProgram = 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)
+parseFunDecl = liftM6 FunDecl
+    (peekPos)
+    (parseIdent)
+       (parseBBraces $ parseSepList CommaToken parseIdent)
+       (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))
+       (FunStmt <$> parseSColon parseFunCall)
        where
                parseSColon :: (Parser Token a) -> Parser Token a
                parseSColon p = p <* satTok SColonToken
@@ -57,8 +58,8 @@ parseStmt = parseIfStmt <|> parseWhileStmt <|>
                 (optional (satTok ElseToken *> (parseBlock<|> parseOneLine))))
 
                parseWhileStmt :: Parser Token Stmt
-               parseWhileStmt = satTok WhileToken *>
-                       (WhileStmt <$> (parseBBraces parseExpr) <*> parseBlock)
+               parseWhileStmt = satTok WhileToken *> (WhileStmt <$> 
+                       (parseBBraces parseExpr) <*> (parseBlock <|> parseOneLine))
 
                parseBlock :: Parser Token [Stmt]
                parseBlock = parseBCBraces (many parseStmt)
@@ -79,7 +80,8 @@ parseFunType = satTok DoubleColonToken *>
                        (Just <$> parseType) <|> pure Nothing
 
 parseVarDecl :: Parser Token VarDecl
-parseVarDecl = liftM3 VarDecl
+parseVarDecl = liftM4 VarDecl
+    peekPos
        (parseType <|> trans1 VarToken VarType )
        (parseIdent <* satTok AssignmentToken)
        (parseExpr <* satTok SColonToken)
@@ -111,27 +113,27 @@ parseExpr = //Operators in order of binding strength
                        trans1 PercentToken BiMod) $ parseBasicExpr
        where
                parseOpR :: (Parser Token Op2) (Parser Token Expr) -> Parser Token Expr
-               parseOpR ops prev = prev >>= \e1->optional (
+               parseOpR ops prev = peekPos >>= \pos-> prev >>= \e1->optional (
                                ops >>= \op->parseOpR ops prev >>= \e->pure (op, e)
-                       ) >>= \moe->pure $ maybe e1 (\(op,e2)->Op2Expr e1 op e2) moe
+                       ) >>= \moe->pure $ maybe e1 (\(op,e2)->Op2Expr pos e1 op e2) moe
 
                parseOpL :: (Parser Token Op2) (Parser Token Expr) -> Parser Token Expr
-               parseOpL ops prev = prev >>= \e1->many (
+               parseOpL ops prev = peekPos >>= \pos-> prev >>= \e1->many (
                                ops >>= \op->prev >>= \e->pure (op, e)
-                       ) >>= \moe->foldM (\e->(\(op,e2)->pure $ Op2Expr e op e2)) e1 moe
+                       ) >>= \moe->foldM (\e->(\(op,e2)->pure $ Op2Expr pos e op e2)) e1 moe
 
                parseBasicExpr :: Parser Token Expr
-               parseBasicExpr =
-                       (TupleExpr <$> (parseTuple parseExpr)) <|>
-                       (FunExpr <$> parseFunCall) <|>
+               parseBasicExpr = peekPos >>= \pos ->
+                       (TupleExpr pos <$> (parseTuple parseExpr)) <|>
+                       (FunExpr pos <$> 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) <|>
-                       (Op1Expr <$> parseOp1 <*> parseExpr) <|>
-                       (VarExpr <$> parseVarDef)
+                       trans1 EmptyListToken (EmptyListExpr pos) <|>
+                       trans1 TrueToken (BoolExpr pos True) <|>
+                       trans1 FalseToken (BoolExpr pos False) <|>
+                       trans2 (NumberToken zero) (\(NumberToken i)->IntExpr pos i) <|>
+                       trans2 (CharToken zero) (\(CharToken c)->CharExpr pos c) <|>
+                       (Op1Expr pos <$> parseOp1 <*> parseExpr) <|>
+                       (VarExpr pos <$> parseVarDef)
 
 parseFunCall :: Parser Token FunCall
 parseFunCall = FunCall <$> parseIdent <*> (parseBBraces $ parseSepList CommaToken parseExpr)
@@ -162,12 +164,18 @@ parseTuple p = satTok BraceOpenToken *>
        (liftM2 (\a->(\b->(a,b))) (p <* satTok CommaToken) p)
        <* satTok BraceCloseToken
 
+trans :: TokenValue (TokenValue -> a) -> Parser Token (Pos, a)
+trans t f = (\(pos,token)->(pos, f token)) <$> satTok t
+
 trans2 :: TokenValue (TokenValue -> a) -> Parser Token a
-trans2 t f = (\(_,token)->f token) <$> satTok t
+trans2 t f = snd <$> trans t f
 
 trans1 :: TokenValue a -> Parser Token a
 trans1 t r = trans2 t $ const r
 
+peekPos :: Parser Token Pos
+peekPos = fst <$> peek
+
 derive gPrint TokenValue
 derive gEq TokenValue
 satTok :: TokenValue -> Parser Token Token
@@ -187,3 +195,6 @@ parseSepList sep p =
 
 parseIdent :: Parser Token String
 parseIdent = trans2 (IdentToken "") (\(IdentToken e).toString e)
+
+//liftM only goes to liftM5
+liftM6 f m1 m2 m3 m4 m5 m6 = f <$> m1 <*> m2 <*> m3 <*> m4 <*> m5 <*> m6