bidispec (empty) → 0.1
raw patch · 4 files changed
+436/−0 lines, 4 filesdep +basedep +bytestringdep +mtlsetup-changed
Dependencies added: base, bytestring, mtl
Files
- LICENSE +165/−0
- Setup.hs +2/−0
- bidispec.cabal +20/−0
- src/Data/BidiSpec.hs +249/−0
+ LICENSE view
@@ -0,0 +1,165 @@+ GNU LESSER GENERAL PUBLIC LICENSE+ Version 3, 29 June 2007++ Copyright (C) 2007 Free Software Foundation, Inc. <http://fsf.org/>+ Everyone is permitted to copy and distribute verbatim copies+ of this license document, but changing it is not allowed.+++ This version of the GNU Lesser General Public License incorporates+the terms and conditions of version 3 of the GNU General Public+License, supplemented by the additional permissions listed below.++ 0. Additional Definitions.++ As used herein, "this License" refers to version 3 of the GNU Lesser+General Public License, and the "GNU GPL" refers to version 3 of the GNU+General Public License.++ "The Library" refers to a covered work governed by this License,+other than an Application or a Combined Work as defined below.++ An "Application" is any work that makes use of an interface provided+by the Library, but which is not otherwise based on the Library.+Defining a subclass of a class defined by the Library is deemed a mode+of using an interface provided by the Library.++ A "Combined Work" is a work produced by combining or linking an+Application with the Library. The particular version of the Library+with which the Combined Work was made is also called the "Linked+Version".++ The "Minimal Corresponding Source" for a Combined Work means the+Corresponding Source for the Combined Work, excluding any source code+for portions of the Combined Work that, considered in isolation, are+based on the Application, and not on the Linked Version.++ The "Corresponding Application Code" for a Combined Work means the+object code and/or source code for the Application, including any data+and utility programs needed for reproducing the Combined Work from the+Application, but excluding the System Libraries of the Combined Work.++ 1. Exception to Section 3 of the GNU GPL.++ You may convey a covered work under sections 3 and 4 of this License+without being bound by section 3 of the GNU GPL.++ 2. Conveying Modified Versions.++ If you modify a copy of the Library, and, in your modifications, a+facility refers to a function or data to be supplied by an Application+that uses the facility (other than as an argument passed when the+facility is invoked), then you may convey a copy of the modified+version:++ a) under this License, provided that you make a good faith effort to+ ensure that, in the event an Application does not supply the+ function or data, the facility still operates, and performs+ whatever part of its purpose remains meaningful, or++ b) under the GNU GPL, with none of the additional permissions of+ this License applicable to that copy.++ 3. Object Code Incorporating Material from Library Header Files.++ The object code form of an Application may incorporate material from+a header file that is part of the Library. You may convey such object+code under terms of your choice, provided that, if the incorporated+material is not limited to numerical parameters, data structure+layouts and accessors, or small macros, inline functions and templates+(ten or fewer lines in length), you do both of the following:++ a) Give prominent notice with each copy of the object code that the+ Library is used in it and that the Library and its use are+ covered by this License.++ b) Accompany the object code with a copy of the GNU GPL and this license+ document.++ 4. Combined Works.++ You may convey a Combined Work under terms of your choice that,+taken together, effectively do not restrict modification of the+portions of the Library contained in the Combined Work and reverse+engineering for debugging such modifications, if you also do each of+the following:++ a) Give prominent notice with each copy of the Combined Work that+ the Library is used in it and that the Library and its use are+ covered by this License.++ b) Accompany the Combined Work with a copy of the GNU GPL and this license+ document.++ c) For a Combined Work that displays copyright notices during+ execution, include the copyright notice for the Library among+ these notices, as well as a reference directing the user to the+ copies of the GNU GPL and this license document.++ d) Do one of the following:++ 0) Convey the Minimal Corresponding Source under the terms of this+ License, and the Corresponding Application Code in a form+ suitable for, and under terms that permit, the user to+ recombine or relink the Application with a modified version of+ the Linked Version to produce a modified Combined Work, in the+ manner specified by section 6 of the GNU GPL for conveying+ Corresponding Source.++ 1) Use a suitable shared library mechanism for linking with the+ Library. A suitable mechanism is one that (a) uses at run time+ a copy of the Library already present on the user's computer+ system, and (b) will operate properly with a modified version+ of the Library that is interface-compatible with the Linked+ Version.++ e) Provide Installation Information, but only if you would otherwise+ be required to provide such information under section 6 of the+ GNU GPL, and only to the extent that such information is+ necessary to install and execute a modified version of the+ Combined Work produced by recombining or relinking the+ Application with a modified version of the Linked Version. (If+ you use option 4d0, the Installation Information must accompany+ the Minimal Corresponding Source and Corresponding Application+ Code. If you use option 4d1, you must provide the Installation+ Information in the manner specified by section 6 of the GNU GPL+ for conveying Corresponding Source.)++ 5. Combined Libraries.++ You may place library facilities that are a work based on the+Library side by side in a single library together with other library+facilities that are not Applications and are not covered by this+License, and convey such a combined library under terms of your+choice, if you do both of the following:++ a) Accompany the combined library with a copy of the same work based+ on the Library, uncombined with any other library facilities,+ conveyed under the terms of this License.++ b) Give prominent notice with the combined library that part of it+ is a work based on the Library, and explaining where to find the+ accompanying uncombined form of the same work.++ 6. Revised Versions of the GNU Lesser General Public License.++ The Free Software Foundation may publish revised and/or new versions+of the GNU Lesser General Public License from time to time. Such new+versions will be similar in spirit to the present version, but may+differ in detail to address new problems or concerns.++ Each version is given a distinguishing version number. If the+Library as you received it specifies that a certain numbered version+of the GNU Lesser General Public License "or any later version"+applies to it, you have the option of following the terms and+conditions either of that published version or of any later version+published by the Free Software Foundation. If the Library as you+received it does not specify a version number of the GNU Lesser+General Public License, you may choose any version of the GNU Lesser+General Public License ever published by the Free Software Foundation.++ If the Library as you received it specifies that a proxy can decide+whether future versions of the GNU Lesser General Public License shall+apply, that proxy's public statement of acceptance of any version is+permanent authorization for you to choose that version for the+Library.
+ Setup.hs view
@@ -0,0 +1,2 @@+import Distribution.Simple+main = defaultMain
+ bidispec.cabal view
@@ -0,0 +1,20 @@+Name: bidispec+Version: 0.1+Synopsis: Specification of generators and parsers+Description:+ This is a generalisation of the idea behind the XML pickle/unpickle+ functions of HXT. It allows to simulatanously specify functions for+ parsing and generating.+License: LGPL+License-file: LICENSE+Category: Data+Author: David Leuschner+Maintainer: David Leuschner <leuschner@openfactis.org>+Build-Type: Simple+Cabal-Version: >= 1.2++Library+ Hs-Source-Dirs: src+ GHC-Options: -Wall+ Build-Depends: base >= 3 && < 4, bytestring, mtl+ Exposed-Modules: Data.BidiSpec
+ src/Data/BidiSpec.hs view
@@ -0,0 +1,249 @@+{-# LANGUAGE GeneralizedNewtypeDeriving #-}+{-# LANGUAGE PatternGuards #-}+{-# LANGUAGE MultiParamTypeClasses #-}+{-# LANGUAGE FlexibleInstances #-}+{-# LANGUAGE FlexibleContexts #-}++module Data.BidiSpec+ (Spec, SpecGen, SpecParser(..)+ ,mkSpec, parseBySpec, genBySpec, runSpecParser, rsGen, rsParse+ ,spGet, spGets, spCheck, spFromMaybe, spFromEither+ ,rsPair, rsTriple, rsQuadruple+ ,rsWrap, rsWrapMaybe, rsWrapEither, rsWrapEither',rsCondSeq+ ,rsChoice, rsAlt, rsTagSwitch, rsSwitch, rsCase, rsCaseConst+ ,rsGetSet,rsCheckSet, rsLift, rsUnit, rsZero, rsWith+ )+where++----------------------------------------+-- STDLIB+----------------------------------------+import Control.Monad (MonadPlus(..), msum, guard, liftM)+import Control.Monad.Error (MonadError(..), Error(..), ErrorT)+import Control.Monad.Trans (MonadTrans, lift)+import Control.Monad.Reader (MonadReader(..), ReaderT, runReaderT, ask, asks)++import Data.Maybe (fromMaybe)+import Data.List (find,elemIndex)++-- ----------------------------------------------------------------------------+-- SpecParser+-- ----------------------------------------------------------------------------+newtype SpecParser s e a+ = SpecParser { unSpecParser :: ReaderT s (Either e) a }+ deriving (Monad, MonadPlus)++instance Error e => MonadError e (SpecParser s e) where+ throwError e = SpecParser $ lift (throwError e)+ catchError (SpecParser ra) f =+ do s <- spGet+ case runReaderT ra s of+ Left e -> f e+ Right x -> return x++instance Error e => MonadReader s (SpecParser s e) where+ ask = SpecParser ask+ local mapSt (SpecParser cont) = SpecParser (local mapSt cont)++runSpecParser :: SpecParser s e a -> s -> Either e a+runSpecParser = runReaderT . unSpecParser++spGet :: Error e => SpecParser s e s+spGet = ask++spGets :: Error e => (s -> a) -> SpecParser s e a+spGets = asks++spCheck :: Error e => (a -> Bool) -> (a -> e) -> a -> SpecParser s e ()+spCheck check mkErr a = guard (check a) `mplus` (throwError (mkErr a))++-- Not exported because the user should supply custom error messages!+spFromMaybe :: Error e => e -> Maybe a -> SpecParser s e a+spFromMaybe e Nothing = throwError e+spFromMaybe _e (Just a) = return a++spFromEither :: Error e => Either e a -> SpecParser s e a+spFromEither (Left e) = throwError e+spFromEither (Right a) = return a++-- ----------------------------------------------------------------------------+-- Spec generator+-- ----------------------------------------------------------------------------++type SpecGen tgt a = tgt -> a -> tgt++-- ----------------------------------------------------------------------------+-- Spec data type+-- ----------------------------------------------------------------------------++data Spec err src tgt a+ = Spec+ { rsGen :: SpecGen tgt a+ , rsParse :: SpecParser src err a }++mkSpec :: SpecParser i e a -> SpecGen o a -> Spec e i o a+mkSpec = flip Spec++parseBySpec :: MonadError e m => Spec e i o a -> i -> m a+parseBySpec sp i =+ case runReaderT (unSpecParser (rsParse sp)) i of+ Left err -> throwError err+ Right res -> return res++genBySpec :: Monad m => Spec e i o a -> o -> a -> m o+genBySpec sp o = return . rsGen sp o+++-- ----------------------------------------------------------------------------+-- Spec combinators+-- ----------------------------------------------------------------------------++rsPair :: Error e => Spec e i o a -> Spec e i o b -> Spec e i o (a,b)+rsPair rsA rsB = mkSpec rsParseDef rsGenDef+ where rsGenDef rout (a,b) = rsGen rsA (rsGen rsB rout b) a+ rsParseDef = do a <- rsParse rsA+ b <- rsParse rsB+ return (a, b)++rsTriple :: Error e =>+ Spec e i o a+ -> Spec e i o b+ -> Spec e i o c+ -> Spec e i o (a,b,c)+rsTriple rsA rsB rsC = mkSpec rsParseDef rsGenDef+ where rsGenDef rout (a,b,c) = rsGen rsC (rsGen rsB (rsGen rsA rout a) b) c+ rsParseDef = do a <- rsParse rsA+ b <- rsParse rsB+ c <- rsParse rsC+ return (a, b, c)++rsQuadruple :: Error e =>+ Spec e i o a+ -> Spec e i o b+ -> Spec e i o c+ -> Spec e i o d+ -> Spec e i o (a,b,c,d)+rsQuadruple rsA rsB rsC rsD = mkSpec rsParseDef rsGenDef+ where rsGenDef rout (a,b,c,d)+ = rsGen rsD (rsGen rsC (rsGen rsB (rsGen rsA rout a) b) c) d+ rsParseDef = do a <- rsParse rsA+ b <- rsParse rsB+ c <- rsParse rsC+ d <- rsParse rsD+ return (a, b, c, d)++rsWrap :: Error e => (a -> b, b -> a) -> Spec e i o a -> Spec e i o b+rsWrap (toB,toA) = rsWrapMaybe (error "BidiSpec: rsWrap") (return . toB, toA)++rsWrapMaybe :: Error e =>+ String -- error message for Maybe case+ -> (a -> Maybe b, b -> a) -- wrappers+ -> Spec e i o a+ -> Spec e i o b+rsWrapMaybe msg (aToB, bToA) rsA = mkSpec rsParseDef rsGenDef+ where rsGenDef rout b = rsGen rsA rout (bToA b)+ rsParseDef = rsParse rsA >>= parseA . aToB+ parseA Nothing = fail (strMsg $ "rsWrapMaybe: " ++ msg)+ parseA (Just b) = return b++rsWrapEither :: Error e =>+ (a -> Either e b, b -> a) -- wrappers+ -> Spec e i o a+ -> Spec e i o b+rsWrapEither (aToB, bToA) rsA = mkSpec rsParseDef rsGenDef+ where rsGenDef rout b = rsGen rsA rout (bToA b)+ rsParseDef = rsParse rsA >>= parseA . aToB+ parseA (Left err) = throwError err+ parseA (Right b) = return b++rsWrapEither' :: (Show l, Error e) =>+ (a -> Either l b, b -> a) -- wrappers+ -> Spec e i o a+ -> Spec e i o b+rsWrapEither' (toB,toA) = rsWrapEither (mapLeft (strMsg . show) . toB, toA)+ where mapLeft f (Left a) = Left (f a)+ mapLeft _f (Right c) = Right c++rsCondSeq :: Error e =>+ Spec e i o b+ -> (b -> a)+ -> Spec e i o a+ -> (a -> Spec e i o b)+ -> Spec e i o b+rsCondSeq pd f pa k = mkSpec rsParseDef rsGenDef+ where rsGenDef rout b = let a = f b+ pb = k a+ in rsGen pa (rsGen pb rout b) a+ rsParseDef = do a <- rsParse pa+ rsParse (k a)+ `mplus` rsParse pd++rsChoice :: Error e =>+ Spec e i o b+ -> Spec e i o a+ -> (a -> Spec e i o b)+ -> Spec e i o b+rsChoice pb = rsCondSeq pb undefined++rsAlt :: Error e => (a -> Int) -> [Spec e i o a] -> Spec e i o a+rsAlt getIdx alts = mkSpec rsParseDef rsGenDef+ where rsGenDef rout a = rsGen (alts !! getIdx a) rout a+ rsParseDef =+ case alts of+ [] -> rsParse rsZero+ (x:xs) -> rsParse (rsChoice (rsAlt getIdx xs) x rsLift)++data SpecCase e i o a = SpecCase { case_value :: a+ , case_spec :: Spec e i o a }++rsCase :: Error e => (a -> b, b -> a) -> Spec e i o a -> SpecCase e i o b+rsCase wrapfuns@(aToB,_bToA) specA = SpecCase value spec+ where value = aToB (error "rsCase: tagging function requires evaluation")+ spec = rsWrap wrapfuns specA++rsCaseConst :: Error e =>+ a -- constant to match/generate+ -> (Spec e i o b -> Spec e i o b) -- continuation+ -> SpecCase e i o a+rsCaseConst a mkRs = rsCase (const a, const undefined) (mkRs (rsLift undef))+ where undef = error "rsCaseConst: this value should have been ignored"++rsSwitch :: (Error e, Show a) => [SpecCase e i o a] -> Spec e i o a+rsSwitch = rsTagSwitch (takeWhile take . dropWhile (=='(') . show)+ where take x = x /= ' ' && x /= ','++rsTagSwitch :: (Error e, Eq t) => (a -> t) -> [SpecCase e i o a] -> Spec e i o a+rsTagSwitch tag cases = mkSpec rsParseDef rsGenDef+ where+ rsParseDef = foldl mplus (fail noMatch) (map (rsParse . case_spec) cases)+ rsGenDef rout a =+ case fmap case_spec $ find ((tag a ==) . tag . case_value) cases of+ Just spec -> rsGen spec rout a+ Nothing -> error noMatch+ noMatch = "rsSwitch: No case matched."++rsGetSet :: Error e => (i -> a) -> (o -> a -> o) -> Spec e i o a+rsGetSet get set = mkSpec rsParseDef rsGenDef+ where rsGenDef = set+ rsParseDef = spGet >>= return . get++rsCheckSet :: Error e =>+ SpecParser i e ()+ -> (o -> o)+ -> Spec e i o a+ -> Spec e i o a+rsCheckSet parser setfun rs = mkSpec rsParseDef rsGenDef+ where rsGenDef rout a = rsGen rs (setfun rout) a+ rsParseDef = parser >> rsParse rs++rsLift :: Error e => a -> Spec e i o a+rsLift x = mkSpec (return x) const++rsZero :: Error e => Spec e i o a+rsZero = mkSpec (fail "rsZero") const++rsUnit :: Error e => Spec e i o ()+rsUnit = rsLift ()++rsWith :: (Spec e i o a -> Spec e i o b) -> Spec e i o a -> Spec e i o b+rsWith = ($)