infix (empty) → 0.1
raw patch · 4 files changed
+987/−0 lines, 4 filesdep +FiniteMapdep +basedep +containerssetup-changed
Dependencies added: FiniteMap, base, containers, haskell-src
Files
- LICENSE +340/−0
- Language/Haskell/Infix.hs +610/−0
- Setup.hs +5/−0
- infix.cabal +32/−0
+ LICENSE view
@@ -0,0 +1,340 @@+ GNU GENERAL PUBLIC LICENSE+ Version 2, June 1991++ Copyright (C) 1989, 1991 Free Software Foundation, Inc.+ 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA+ Everyone is permitted to copy and distribute verbatim copies+ of this license document, but changing it is not allowed.++ Preamble++ The licenses for most software are designed to take away your+freedom to share and change it. By contrast, the GNU General Public+License is intended to guarantee your freedom to share and change free+software--to make sure the software is free for all its users. This+General Public License applies to most of the Free Software+Foundation's software and to any other program whose authors commit to+using it. (Some other Free Software Foundation software is covered by+the GNU Library General Public License instead.) You can apply it to+your programs, too.++ When we speak of free software, we are referring to freedom, not+price. 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+ Language/Haskell/Infix.hs view
@@ -0,0 +1,610 @@+{-------------------------------------------------------------------------------++ Module: Language.Haskell.Infix++ Description: The Haskell Parser does not consider the fixity+ of operators when parsing infix applications.+ All infix applications are thus parsed as+ if the operators were all left associative with+ the same precedence.++ This module contains code for re-parsing infix+ applications taking into account the fixity of+ operators.++ The important algorithm is the well known+ operator precedence parsing algorithm. See+ comments in the code for more detailed+ information.++ Primary Authors: Bernie Pope (bjpop@cs.mu.oz.au)++-------------------------------------------------------------------------------}+++module Language.Haskell.Infix ( infixer+ , insertTopInfixDecls+ , InfixMap+ , plusInfixMap+ , Fixity (..)+ , showInfixMap+ , infixMapToList+ , emptyInfixMap+ ) where++import Language.Haskell.Syntax+import Data.FiniteMap++--------------------------------------------------------------------------------++-- the fixity information+data Fixity = Fixity { fixity_assoc :: HsAssoc,+ fixity_prec :: Int }+ deriving Show++-- a mapping from qualified operator names to fixity information+type InfixMap = FiniteMap HsQName Fixity++plusInfixMap :: InfixMap -> InfixMap -> InfixMap+plusInfixMap = plusFM++emptyInfixMap :: InfixMap+emptyInfixMap = emptyFM++infixMapToList :: InfixMap -> [(HsQName, Fixity)]+infixMapToList = fmToList++-- pretty crude illustration of infix map+showInfixMap :: InfixMap -> String+showInfixMap infixMap+ = unlines $ map show mapList+ where+ mapList = infixMapToList infixMap++-- fix up infix applications in a list of decls, to be called with+-- the topmost declarations in a module+infixer :: InfixMap -> [HsDecl] -> [HsDecl]+infixer infixMap decls+ = runInfix infixMap $ mapM infixDecl decls++-- this this the default fixity of an operator, to be used if the+-- operator does not have a corresponding fixity declaration+defaultFixity :: Fixity+defaultFixity = Fixity { fixity_assoc = HsAssocLeft, fixity_prec = 9 }++--------------------------------------------------------------------------------++-- a monad for passing the infix map around++data State = State { stateInfixMap :: InfixMap }++newtype Infix a = Infix (State -> (a, State))++instance Monad Infix where+ return a+ = Infix (\state -> (a, state))+ Infix comp >>= fun+ = Infix (\state ->+ let (result, newState) = comp state+ Infix comp' = fun result+ in comp' newState)++runInfix :: InfixMap -> Infix a -> a+runInfix infixMap (Infix comp)+ = result+ where+ (result, _newState) = comp (State {stateInfixMap = infixMap})++select :: (State -> a) -> Infix a+select selector = Infix (\state -> (selector state, state))++updateState :: (State -> State) -> Infix ()+updateState f = Infix (\state -> ((), f state))++getInfixMap :: Infix InfixMap+getInfixMap = select stateInfixMap++getFixityQOp :: HsQOp -> Infix Fixity+getFixityQOp op+ = getFixityQName $ qNameFromQOp op++getFixityQName :: HsQName -> Infix Fixity+-- special consideration of (:) because it is not+-- explicitly given fixity info in the Prelude+-- this is the only one that needs special treatment+getFixityQName (Special HsCons)+ = return $ Fixity {fixity_assoc = HsAssocRight, fixity_prec = 5}+getFixityQName name+ = do infixMap <- getInfixMap+ case lookupFM infixMap name of+ Nothing -> return defaultFixity+ Just fixity -> return fixity++updateInfixMap :: [HsDecl] -> Infix ()+updateInfixMap decls+ = do oldInfixMap <- getInfixMap+ let newInfixMap = insertLocalInfixDecls oldInfixMap decls+ updateState (\state -> state {stateInfixMap = newInfixMap})++qNameFromQOp :: HsQOp -> HsQName+qNameFromQOp (HsQVarOp qName) = qName+qNameFromQOp (HsQConOp qName) = qName++nameFromOp :: HsOp -> HsName+nameFromOp (HsVarOp name) = name+nameFromOp (HsConOp name) = name++--------------------------------------------------------------------------------++-- crawl over expressions++infixExp :: HsExp -> Infix HsExp+infixExp exp@(HsVar _) = return exp+infixExp exp@(HsCon _) = return exp+infixExp exp@(HsLit _) = return exp+infixExp exp@(HsInfixApp _ _ _)+ = do infixList <- hsExpToInfixList exp+ let eFix = opPrecParse HsInfixApp infixList+ return eFix+infixExp (HsApp e1 e2)+ = do e1Fix <- infixExp e1+ e2Fix <- infixExp e2+ return $ HsApp e1Fix e2Fix+infixExp (HsNegApp e)+ = do eFix <- infixExp e+ return $ HsNegApp eFix+infixExp (HsLambda sloc pats e)+ = do patsFix <- mapM infixPat pats+ eFix <- infixExp e+ return $ HsLambda sloc patsFix eFix+infixExp (HsLet decls e)+ = do updateInfixMap decls+ eFix <- infixExp e+ _ <- mapM infixDecl decls+ return $ HsLet decls eFix+infixExp (HsIf e1 e2 e3)+ = do e1Fix <- infixExp e1+ e2Fix <- infixExp e2+ e3Fix <- infixExp e3+ return $ HsIf e1Fix e2Fix e3Fix+infixExp (HsCase e alts)+ = do eFix <- infixExp e+ altsFix <- mapM infixAlt alts+ return $ HsCase eFix altsFix+infixExp (HsDo stmts)+ = do stmtsFix <- mapM infixStmt stmts+ return $ HsDo stmtsFix+infixExp (HsTuple exps)+ = do expsFix <- mapM infixExp exps+ return $ HsTuple expsFix+infixExp (HsList exps)+ = do expsFix <- mapM infixExp exps+ return $ HsList expsFix+infixExp (HsParen exp)+ = do expFix <- infixExp exp+ return $ HsParen expFix+infixExp (HsLeftSection e qop)+ = do eFix <- infixExp e+ return $ HsLeftSection eFix qop+infixExp (HsRightSection qop e)+ = do eFix <- infixExp e+ return $ HsRightSection qop eFix+infixExp (HsRecConstr qName fieldUpdates)+ = do fixFieldUpdates <- mapM infixFieldUpdate fieldUpdates+ return $ HsRecConstr qName fixFieldUpdates+infixExp (HsRecUpdate e fieldUpdates)+ = do eFix <- infixExp e+ fixFieldUpdates <- mapM infixFieldUpdate fieldUpdates+ return $ HsRecUpdate eFix fixFieldUpdates+infixExp (HsEnumFrom e)+ = do eFix <- infixExp e+ return $ HsEnumFrom eFix+infixExp (HsEnumFromTo e1 e2)+ = do e1Fix <- infixExp e1+ e2Fix <- infixExp e2+ return $ HsEnumFromTo e1Fix e2Fix+infixExp (HsEnumFromThen e1 e2)+ = do e1Fix <- infixExp e1+ e2Fix <- infixExp e2+ return $ HsEnumFromThen e1Fix e2Fix+infixExp (HsEnumFromThenTo e1 e2 e3)+ = do e1Fix <- infixExp e1+ e2Fix <- infixExp e2+ e3Fix <- infixExp e3+ return $ HsEnumFromThenTo e1Fix e2Fix e3Fix+infixExp (HsListComp e stmts)+ = do eFix <- infixExp e+ stmtsFix <- mapM infixStmt stmts+ return $ HsListComp eFix stmtsFix+infixExp (HsExpTypeSig sloc e qualType)+ = do eFix <- infixExp e+ return $ HsExpTypeSig sloc eFix qualType+infixExp (HsAsPat name e)+ = do eFix <- infixExp e+ return $ HsAsPat name eFix+infixExp HsWildCard = return HsWildCard+infixExp (HsIrrPat e)+ = do eFix <- infixExp e+ return $ HsIrrPat eFix+++--------------------------------------------------------------------------------++-- crawl over patterns++infixPat :: HsPat -> Infix HsPat+infixPat pat@(HsPVar _) = return pat+infixPat pat@(HsPLit _) = return pat+infixPat (HsPNeg pat)+ = do pFix <- infixPat pat+ return $ HsPNeg pFix+infixPat pat@(HsPInfixApp _ _ _)+ = do infixList <- hsPatToInfixList pat+ let pFix = opPrecParse HsPInfixApp infixList+ return pFix+infixPat (HsPApp qName pats)+ = do patsFix <- mapM infixPat pats+ return $ HsPApp qName patsFix+infixPat (HsPTuple pats)+ = do patsFix <- mapM infixPat pats+ return $ HsPTuple patsFix+infixPat (HsPList pats)+ = do patsFix <- mapM infixPat pats+ return $ HsPList patsFix+infixPat (HsPParen pat)+ = do pFix <- infixPat pat+ return $ HsPParen pFix+infixPat (HsPRec qName patFields)+ = do fieldsFix <- mapM infixPatField patFields+ return $ HsPRec qName fieldsFix+infixPat (HsPAsPat name pat)+ = do pFix <- infixPat pat+ return $ HsPAsPat name pFix+infixPat HsPWildCard = return HsPWildCard+infixPat (HsPIrrPat pat)+ = do pFix <- infixPat pat+ return $ HsPIrrPat pFix++-- pattern fields+infixPatField :: HsPatField -> Infix HsPatField+infixPatField (HsPFieldPat qName pat)+ = do pFix <- infixPat pat+ return $ HsPFieldPat qName pFix++--------------------------------------------------------------------------------++-- crawl over alternatives++infixAlt :: HsAlt -> Infix HsAlt+infixAlt (HsAlt sloc pat guardedAlts decls)+ = do pFix <- infixPat pat+ fixAlts <- infixGuardedAlts guardedAlts+ fixDecls <- mapM infixDecl decls+ return $ HsAlt sloc pFix fixAlts fixDecls++infixGuardedAlts :: HsGuardedAlts -> Infix HsGuardedAlts+infixGuardedAlts (HsUnGuardedAlt e)+ = do eFix <- infixExp e+ return $ HsUnGuardedAlt eFix+infixGuardedAlts (HsGuardedAlts gAlts)+ = do fixGAlts <- mapM infixGuardedAlt gAlts+ return $ HsGuardedAlts fixGAlts++infixGuardedAlt :: HsGuardedAlt -> Infix HsGuardedAlt+infixGuardedAlt (HsGuardedAlt sloc e1 e2)+ = do e1Fix <- infixExp e1+ e2Fix <- infixExp e2+ return $ HsGuardedAlt sloc e1Fix e2Fix++--------------------------------------------------------------------------------++-- crawl over statements++infixStmt :: HsStmt -> Infix HsStmt+infixStmt (HsGenerator sloc pat e)+ = do pFix <- infixPat pat+ eFix <- infixExp e+ return $ HsGenerator sloc pFix eFix+infixStmt (HsQualifier e)+ = do eFix <- infixExp e+ return $ HsQualifier eFix+infixStmt (HsLetStmt decls)+ = do updateInfixMap decls+ declsFix <- mapM infixDecl decls+ return $ HsLetStmt declsFix++--------------------------------------------------------------------------------++-- crawl over field updates++infixFieldUpdate :: HsFieldUpdate -> Infix HsFieldUpdate+infixFieldUpdate (HsFieldUpdate qName e)+ = do eFix <- infixExp e+ return $ HsFieldUpdate qName eFix++--------------------------------------------------------------------------------++-- crawl over declarations++infixDecl :: HsDecl -> Infix HsDecl+infixDecl (HsFunBind matches)+ = do fixMatches <- mapM infixMatch matches+ return $ HsFunBind fixMatches+infixDecl (HsPatBind sloc pat rhs decls)+ = do pFix <- infixPat pat+ updateInfixMap decls+ fixRhs <- infixRhs rhs+ fixDecls <- mapM infixDecl decls+ return $ HsPatBind sloc pFix fixRhs fixDecls+infixDecl (HsClassDecl sloc cntxt className args decls)+ = do declsFix <- mapM infixDecl decls+ return $ HsClassDecl sloc cntxt className args declsFix+infixDecl (HsInstDecl sloc cntxt className args decls)+ = do declsFix <- mapM infixDecl decls+ return $ HsInstDecl sloc cntxt className args declsFix+infixDecl otherDecl = return otherDecl++-- matches+infixMatch :: HsMatch -> Infix HsMatch+infixMatch (HsMatch sloc name pats rhs decls)+ = do patsFix <- mapM infixPat pats+ updateInfixMap decls+ fixRhs <- infixRhs rhs+ fixDecls <- mapM infixDecl decls+ return $ HsMatch sloc name patsFix fixRhs fixDecls++-- rhs+infixRhs :: HsRhs -> Infix HsRhs+infixRhs (HsUnGuardedRhs e)+ = do eFix <- infixExp e+ return $ HsUnGuardedRhs eFix+infixRhs (HsGuardedRhss rhss)+ = do rhssFix <- mapM infixGuardedRhs rhss+ return $ HsGuardedRhss rhssFix++-- guarded rhs+infixGuardedRhs :: HsGuardedRhs -> Infix HsGuardedRhs+infixGuardedRhs (HsGuardedRhs sloc e1 e2)+ = do e1Fix <- infixExp e1+ e2Fix <- infixExp e2+ return $ HsGuardedRhs sloc e1Fix e2Fix++--------------------------------------------------------------------------------++-- add new infix rules to an existing table+-- this is only for local infix decls (those not at the top-level of a+-- module). These decls only cause unqualified names to be entered+-- into the infix map.++insertLocalInfixDecls :: InfixMap -> [HsDecl] -> InfixMap+insertLocalInfixDecls imap [] = imap+insertLocalInfixDecls imap (HsInfixDecl _ assoc prec ops : decls)+ = insertLocalInfixDecls (insertLocalOps thisFixity ops imap) decls+ where+ thisFixity = Fixity { fixity_assoc = assoc, fixity_prec = prec }+ insertLocalOps :: Fixity -> [HsOp] -> InfixMap -> InfixMap+ insertLocalOps _fixity [] imap = imap+ insertLocalOps fixity (op:ops) infixMap+ = let opName = nameFromOp op+ map1 = addToFM infixMap (UnQual opName) fixity+ in insertLocalOps fixity ops map1+insertLocalInfixDecls imap (_ : decls)+ = insertLocalInfixDecls imap decls++-- as above but for top-level infix decls (which (sadly) can also occur inside+-- class declarations))+-- Top level infix decls cause unqualified AND+-- qualified names to be entered into the infix map+insertTopInfixDecls :: Module -> InfixMap -> [HsDecl] -> InfixMap+insertTopInfixDecls _ imap [] = imap+insertTopInfixDecls modName imap (HsInfixDecl _ assoc prec ops : decls)+ = insertTopInfixDecls modName (insertTopOps modName thisFixity ops imap) decls+ where+ thisFixity :: Fixity+ thisFixity = Fixity { fixity_assoc = assoc, fixity_prec = prec }+ insertTopOps :: Module -> Fixity -> [HsOp] -> InfixMap -> InfixMap+ insertTopOps _ _fixity [] imap = imap+ insertTopOps modName fixity (op:ops) infixMap+ = let opName = nameFromOp op+ -- insert qualified and unqualified versions of the name+ -- into the infix table+ map1 = addToFM infixMap (UnQual opName) fixity+ map2 = addToFM map1 (Qual modName $ opName) fixity+ in insertTopOps modName fixity ops map2+-- class decls can have infix decls and these are treated in the same way+-- as top-level infix decls+insertTopInfixDecls modName imap (HsClassDecl _sloc _cntxt _name _args classDecls : decls)+ = insertTopInfixDecls modName (insertTopInfixDecls modName imap classDecls) decls+-- step over any other decl+insertTopInfixDecls modName imap (_ : decls)+ = insertTopInfixDecls modName imap decls++{-------------------------------------------------------------------------------++ Here is the important part.++ The parser does not take the fixity (precedence and associativity) of+ infix operators into account when it parses a module. This is because+ imported operators may have their own fixity, so to know all the fixity+ information for a single module, the parser would have to know the fixity+ information for imported modules - which would require partial parsing of+ imported modules, and would be a mess.++ Instead it parses all infix applications as if they were left associative,+ with each operator having the same precedence, for example:++ 1 + 2 ^ 4 * 6 - 8++ would be parsed as:++ ((((1 + 2) ^ 4) * 6) - 8)++ This is clearly wrong. To fix this we re-parse the expression taking fixity+ into account.++ The first step is to convert it into a more convenient form: from a parse tree+ to a list of expressions (alternating between expression and operator):++ [Arg 1,+ Op (+) HsAssocLeft 6,+ Arg 2,+ Op (^) HsAssocRight 8,+ Arg 4,+ Op (*) HsAssocLeft 7,+ Arg 6,+ Op (-) HsAssocLeft 6,+ Arg 8]++ The conversion is done by hsExpToInfixList. This stage is not really necessary.+ However, I feel that it does contribute to the clarity of the program, and+ correctness is more important than efficiency here.++ The second step is to reparse this expression using the well known+ operator precedence parsing technique.++ The basic idea is to introduce two stacks: one for expressions (the arguments+ in between the operators), and one for operators. Parsing alternates between dealing with+ the next expression and dealing with the next operator.++ Expressions are always pushed onto the stack when they are encountered as the next+ item in the input list.++ Operators are pushed onto the operator stack iff they have a higher precedence than+ the operator on top of the stack (or the stack is empty).++ If the next operator has a lower precedence than the top operator in the operator stack,+ a reduction is performed. The top operator on the stack is applied to the two topmost+ expressions on the expression stack, forming a new experssion (an infix application).+ This new expression replaces the two top expressions on the expression stack, we then+ continue.++ If the next operator and the top operator have the same precedence, then their+ associativity determines what happens. If they are both left associative then a+ reduction is performed. If they are both right associative then the next operator+ is shifted. If they are a mixture of anything else (left, right, non-assoc) then+ a syntax error has occurred.++ Two non-associative operators are allowed in sequence iff they have different precedences.++ eStack opStack input+ {} {} 1 + 2 ^ 4 * 6 - 8+ 1 {} + 2 ^ 4 * 6 - 8 (shift exp)+ 1 + 2 ^ 4 * 6 - 8 (shift op)+ 1,2 + ^ 4 * 6 - 8 (shift exp)+ 1,2 +,^ 4 * 6 - 8 (shift op)+ 1,2,4 +,^ * 6 - 8 (shift exp)+ 1,(2^4) + * 6 - 8 (reduce)+ 1,(2^4) +,* 6 - 8 (shift op)+ 1,(2^4),6 +,* - 8 (shift exp)+ 1,((2^4)*6) + - 8 (reduce)+ (1+((2^4)*6)) {} - 8 (reduce, b/c +,- are left associative)+ (1+((2^4)*6)) - 8 (shift op)+ (1+((2^4)*6)),8 - {} (shift exp)+ ((1+((2^4)*6))-8) {} {} (reduce)++ The final state MUST have exactly one expression in the expression stack,+ zero operators in the operator stack, and zero items left in the input.++ All other final states are horrible errors, though in our case some parsing+ has already been done, and so some types of error will be caught earlier.++ Similar reasoning to the above applies for infix pattern applications,+ as in:++ foo (x:y:z:zs) is parsed as foo ((((x:y):z):zs)), which is wrong.+ The precedence parser has been made sufficiently generic to reparse+ expressions and patterns.++--------------------------------------------------------------------------------}++{- here we just convert the syntax trees of patterns and expressions into+ something more convenient to manipulate for the later stage of+ precedence parsing -}++-- an operator or an argument (for an operator)+-- generalised to support expressions and patterns+data InfixExp op arg+ = Op op Fixity | Arg arg+ deriving Show++hsExpToInfixList :: HsExp -> Infix [InfixExp HsQOp HsExp]+hsExpToInfixList exp+ = hsExpToInfixAcc exp []+ where+ hsExpToInfixAcc :: HsExp -> [InfixExp HsQOp HsExp] -> Infix [InfixExp HsQOp HsExp]+ hsExpToInfixAcc (HsInfixApp e1 op e2) acc+ = do fixity <- getFixityQOp op+ e2Fix <- infixExp e2+ hsExpToInfixAcc e1 (Op op fixity : Arg e2Fix : acc)+ hsExpToInfixAcc exp acc+ = do eFix <- infixExp exp+ return $ Arg eFix : acc++-- as above but for patterns+hsPatToInfixList :: HsPat -> Infix [InfixExp HsQName HsPat]+hsPatToInfixList pat+ = hsPatToInfixAcc pat []+ where+ hsPatToInfixAcc :: HsPat -> [InfixExp HsQName HsPat] -> Infix [InfixExp HsQName HsPat]+ hsPatToInfixAcc (HsPInfixApp p1 op p2) acc+ = do fixity <- getFixityQName op+ p2Fix <- infixPat p2+ hsPatToInfixAcc p1 (Op op fixity : Arg p2Fix : acc)+ hsPatToInfixAcc pat acc+ = do pFix <- infixPat pat+ return $ Arg pFix : acc++--------------------------------------------------------------------------------++-- operator precedence parsing++opPrecParse :: (arg -> op -> arg -> arg) -> [InfixExp op arg] -> arg+opPrecParse combiner exps+ = reparseInfix combiner exps [] []+ where+ reparseInfix :: (arg -> op -> arg -> arg)+ -> [InfixExp op arg]+ -> [(op, Fixity)]+ -> [arg]+ -> arg+ -- successful termination+ reparseInfix _combiner [] [] [arg] = arg+ -- consume the remaining operators that have been stacked+ reparseInfix combiner [] ((op,_fixity):opStack) (a1:a2:argStack)+ = reparseInfix combiner [] opStack (combiner a2 op a1 : argStack)+ -- always shift the expressions+ reparseInfix combiner (Arg a : args) opStack argStack+ = reparseInfix combiner args opStack (a : argStack)+ -- empty operator stack, just shift the operator+ reparseInfix combiner (Op thisOp thisFixity : rest) [] argStack+ = reparseInfix combiner rest [(thisOp,thisFixity)] argStack+ reparseInfix combiner (Op thisOp thisFixity : rest) (topOpStack:opStack) (topArg1:topArg2:argStack)+ -- shift the operator+ | thisPrec > topPrec+ = reparseInfix combiner rest ((thisOp,thisFixity):topOpStack:opStack)+ (topArg1:topArg2:argStack)+ -- reduce+ | thisPrec < topPrec+ = reparseInfix combiner (Op thisOp thisFixity : rest) opStack+ (combiner topArg2 topOp topArg1 : argStack)+ -- equal precedence, check the associativity+ | otherwise+ = case (thisAssoc, topAssoc) of+ -- reduce+ (HsAssocLeft, HsAssocLeft)+ -> reparseInfix combiner (Op thisOp thisFixity : rest) opStack+ (combiner topArg2 topOp topArg1 : argStack)+ -- shift+ (HsAssocRight, HsAssocRight)+ -> reparseInfix combiner rest ((thisOp,thisFixity):topOpStack:opStack)+ (topArg1:topArg2:argStack)+ -- this error needs fixing+ _ -> error "Syntax error"+ where+ (topOp, topFixity) = topOpStack+ topAssoc = fixity_assoc topFixity+ topPrec = fixity_prec topFixity+ thisAssoc = fixity_assoc thisFixity+ thisPrec = fixity_prec thisFixity+ -- XXX this error needs fixing+ reparseInfix _ _ _ _ = error "Syntax error"
+ Setup.hs view
@@ -0,0 +1,5 @@+#!/usr/bin/runhaskell++import Distribution.Simple++main = defaultMainWithHooks defaultUserHooks
+ infix.cabal view
@@ -0,0 +1,32 @@+name: infix+version: 0.1+synopsis: Infix expression re-parsing (for HsParser library)+description: The Haskell parser does not consider the fixity+ of operators when parsing infix applications.+ All infix applications are thus parsed as+ if the operators were all left associative with+ the same precedence.++ This module contains code for re-parsing infix+ applications taking into account the fixity of+ operators.++ The important algorithm is the well known+ operator precedence parsing algorithm. See+ comments in the code for more detailed+ information.+category: Parsing+license: GPL+license-file: LICENSE+author: Bernie Pope <bjpop@csse.unimelb.edu.au>+maintainer: None+homepage: http://www.cs.mu.oz.au/~bjpop/code.html++build-depends: base, containers, haskell-src, FiniteMap+build-type: Simple+tested-with: GHC==6.5++exposed-modules: Language.Haskell.Infix++ghc-options: -O2 -Wall -optl-Wl,-s+ghc-prof-options: -prof -auto-all