dynamic-state-0.2.2.0/0000755000000000000000000000000012702027741012603 5ustar0000000000000000dynamic-state-0.2.2.0/Setup.hs0000644000000000000000000000005612702027741014240 0ustar0000000000000000import Distribution.Simple main = defaultMain dynamic-state-0.2.2.0/LICENSE0000644000000000000000000004311012702027741013607 0ustar0000000000000000 GNU GENERAL PUBLIC LICENSE Version 2, June 1991 Copyright (C) 1989, 1991 Free Software Foundation, Inc. 59 Temple Place, Suite 330, Boston, MA 02111-1307 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. Our General Public Licenses are designed to make sure that you have the freedom to distribute copies of free software (and charge for this service if you wish), that you receive source code or can get it if you want it, that you can change the software or use pieces of it in new free programs; and that you know you can do these things. To protect your rights, we need to make restrictions that forbid anyone to deny you these rights or to ask you to surrender the rights. These restrictions translate to certain responsibilities for you if you distribute copies of the software, or if you modify it. For example, if you distribute copies of such a program, whether gratis or for a fee, you must give the recipients all the rights that you have. You must make sure that they, too, receive or can get the source code. And you must show them these terms so they know their rights. We protect your rights with two steps: (1) copyright the software, and (2) offer you this license which gives you legal permission to copy, distribute and/or modify the software. Also, for each author's protection and ours, we want to make certain that everyone understands that there is no warranty for this free software. If the software is modified by someone else and passed on, we want its recipients to know that what they have is not the original, so that any problems introduced by others will not reflect on the original authors' reputations. Finally, any free program is threatened constantly by software patents. We wish to avoid the danger that redistributors of a free program will individually obtain patent licenses, in effect making the program proprietary. To prevent this, we have made it clear that any patent must be licensed for everyone's free use or not licensed at all. The precise terms and conditions for copying, distribution and modification follow. GNU GENERAL PUBLIC LICENSE TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION 0. This License applies to any program or other work which contains a notice placed by the copyright holder saying it may be distributed under the terms of this General Public License. The "Program", below, refers to any such program or work, and a "work based on the Program" means either the Program or any derivative work under copyright law: that is to say, a work containing the Program or a portion of it, either verbatim or with modifications and/or translated into another language. (Hereinafter, translation is included without limitation in the term "modification".) Each licensee is addressed as "you". Activities other than copying, distribution and modification are not covered by this License; they are outside its scope. The act of running the Program is not restricted, and the output from the Program is covered only if its contents constitute a work based on the Program (independent of having been made by running the Program). Whether that is true depends on what the Program does. 1. You may copy and distribute verbatim copies of the Program's source code as you receive it, in any medium, provided that you conspicuously and appropriately publish on each copy an appropriate copyright notice and disclaimer of warranty; keep intact all the notices that refer to this License and to the absence of any warranty; and give any other recipients of the Program a copy of this License along with the Program. You may charge a fee for the physical act of transferring a copy, and you may at your option offer warranty protection in exchange for a fee. 2. You may modify your copy or copies of the Program or any portion of it, thus forming a work based on the Program, and copy and distribute such modifications or work under the terms of Section 1 above, provided that you also meet all of these conditions: a) You must cause the modified files to carry prominent notices stating that you changed the files and the date of any change. b) You must cause any work that you distribute or publish, that in whole or in part contains or is derived from the Program or any part thereof, to be licensed as a whole at no charge to all third parties under the terms of this License. c) If the modified program normally reads commands interactively when run, you must cause it, when started running for such interactive use in the most ordinary way, to print or display an announcement including an appropriate copyright notice and a notice that there is no warranty (or else, saying that you provide a warranty) and that users may redistribute the program under these conditions, and telling the user how to view a copy of this License. (Exception: if the Program itself is interactive but does not normally print such an announcement, your work based on the Program is not required to print an announcement.) These requirements apply to the modified work as a whole. If identifiable sections of that work are not derived from the Program, and can be reasonably considered independent and separate works in themselves, then this License, and its terms, do not apply to those sections when you distribute them as separate works. But when you distribute the same sections as part of a whole which is a work based on the Program, the distribution of the whole must be on the terms of this License, whose permissions for other licensees extend to the entire whole, and thus to each and every part regardless of who wrote it. 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If the Program specifies a version number of this License which applies to it and "any later version", you have the option of following the terms and conditions either of that version or of any later version published by the Free Software Foundation. If the Program does not specify a version number of this License, you may choose any version ever published by the Free Software Foundation. 10. If you wish to incorporate parts of the Program into other free programs whose distribution conditions are different, write to the author to ask for permission. For software which is copyrighted by the Free Software Foundation, write to the Free Software Foundation; we sometimes make exceptions for this. Our decision will be guided by the two goals of preserving the free status of all derivatives of our free software and of promoting the sharing and reuse of software generally. NO WARRANTY 11. BECAUSE THE PROGRAM IS LICENSED FREE OF CHARGE, THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY APPLICABLE LAW. EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE PROGRAM IS WITH YOU. SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING, REPAIR OR CORRECTION. 12. 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It is safest to attach them to the start of each source file to most effectively convey the exclusion of warranty; and each file should have at least the "copyright" line and a pointer to where the full notice is found. Copyright (C) This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA Also add information on how to contact you by electronic and paper mail. If the program is interactive, make it output a short notice like this when it starts in an interactive mode: Gnomovision version 69, Copyright (C) year name of author Gnomovision comes with ABSOLUTELY NO WARRANTY; for details type `show w'. This is free software, and you are welcome to redistribute it under certain conditions; type `show c' for details. The hypothetical commands `show w' and `show c' should show the appropriate parts of the General Public License. Of course, the commands you use may be called something other than `show w' and `show c'; they could even be mouse-clicks or menu items--whatever suits your program. You should also get your employer (if you work as a programmer) or your school, if any, to sign a "copyright disclaimer" for the program, if necessary. Here is a sample; alter the names: Yoyodyne, Inc., hereby disclaims all copyright interest in the program `Gnomovision' (which makes passes at compilers) written by James Hacker. , 1 April 1989 Ty Coon, President of Vice This General Public License does not permit incorporating your program into proprietary programs. If your program is a subroutine library, you may consider it more useful to permit linking proprietary applications with the library. If this is what you want to do, use the GNU Library General Public License instead of this License. dynamic-state-0.2.2.0/dynamic-state.cabal0000644000000000000000000000151612702027741016334 0ustar0000000000000000name: dynamic-state version: 0.2.2.0 synopsis: Optionally serializable dynamic state keyed by type description: Optionally serializable dynamic state keyed by type license: GPL-2 license-file: LICENSE author: Carter Charbonneau maintainer: zcarterc@gmail.com category: Yi, Data build-type: Simple cabal-version: >=1.10 library ghc-options: -Wall exposed-modules: Data.ConcreteTypeRep Data.DynamicState Data.DynamicState.Serializable build-depends: base >=4.6 && <5.0 , binary , bytestring , unordered-containers , hashable hs-source-dirs: src default-language: Haskell2010 source-repository head type: git location: https://github.com/yi-editor/dynamic-state.git dynamic-state-0.2.2.0/src/0000755000000000000000000000000012702027741013372 5ustar0000000000000000dynamic-state-0.2.2.0/src/Data/0000755000000000000000000000000012702027741014243 5ustar0000000000000000dynamic-state-0.2.2.0/src/Data/DynamicState.hs0000644000000000000000000000246312702027741017171 0ustar0000000000000000{-# LANGUAGE ScopedTypeVariables #-} {-# LANGUAGE DeriveDataTypeable #-} {-# OPTIONS_HADDOCK show-extensions #-} -- | -- Module : Data.DynamicState -- License : GPL2 -- Maintainer : zcarterc@gmail.com -- Stability : experimental -- Portability : portable -- -- This module implements a simple HashMap ConcreteTypeRep Dynamic module Data.DynamicState ( DynamicState(..), getDyn, setDyn, _dyn ) where import Data.Dynamic import Data.HashMap.Strict as M import Data.ConcreteTypeRep import Data.Monoid import Control.Applicative -- | An extensible record, indexed by type newtype DynamicState = DynamicState { unDynamicState :: M.HashMap ConcreteTypeRep Dynamic } deriving (Typeable) instance Monoid DynamicState where mappend (DynamicState a) (DynamicState b) = DynamicState (mappend a b) mempty = DynamicState mempty getDyn :: forall a. Typeable a => DynamicState -> Maybe a getDyn (DynamicState ds) = M.lookup (cTypeOf (undefined :: a)) ds >>= fromDynamic setDyn :: forall a. Typeable a => DynamicState -> a -> DynamicState setDyn (DynamicState ds) x = DynamicState $ M.insert (cTypeOf (undefined :: a)) (toDyn x) ds -- | Lens with default value _dyn :: (Typeable a, Functor f) => a -> (a -> f a) -> DynamicState -> f DynamicState _dyn def afb s = setDyn s <$> afb (maybe def id $ getDyn s) dynamic-state-0.2.2.0/src/Data/ConcreteTypeRep.hs0000644000000000000000000001051112702027741017650 0ustar0000000000000000{-# LANGUAGE DeriveDataTypeable, GeneralizedNewtypeDeriving, CPP #-} {- | Copyright (c)2011, Reiner Pope All rights reserved. Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met: * Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer. * Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution. * Neither the name of Reiner Pope nor the names of other contributors may be used to endorse or promote products derived from this software without specific prior written permission. THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. This module defines 'Binary' and 'Hashable' instances for 'TypeRep'. These are defined on a newtype of 'TypeRep', namely 'ConcreteTypeRep', for two purposes: * to avoid making orphan instances * the 'Hashable' instance for 'ConcreteTypeRep' may not be pure enough for some people's tastes. As usual with 'Typeable', this module will typically be used with some variant of @Data.Dynamic@. Two possible uses of this module are: * making hashmaps: @HashMap 'ConcreteTypeRep' Dynamic@ * serializing @Dynamic@s. -} module Data.ConcreteTypeRep ( ConcreteTypeRep, cTypeOf, toTypeRep, fromTypeRep, ) where import Data.Typeable import Data.Typeable.Internal import Data.Hashable import Data.Binary import Control.Applicative((<$>)) -- | Abstract type providing the functionality of 'TypeRep', but additionally supporting hashing and serialization. -- -- The 'Eq' instance is just the 'Eq' instance for 'TypeRep', so an analogous guarantee holds: @'cTypeOf' a == 'cTypeOf' b@ if and only if @a@ and @b@ have the same type. -- The hashing and serialization functions preserve this equality. newtype ConcreteTypeRep = CTR { unCTR :: TypeRep } deriving(Eq, Typeable) -- | \"Concrete\" version of 'typeOf'. cTypeOf :: Typeable a => a -> ConcreteTypeRep cTypeOf = fromTypeRep . typeOf -- | Converts to the underlying 'TypeRep' toTypeRep :: ConcreteTypeRep -> TypeRep toTypeRep = unCTR -- | Converts from the underlying 'TypeRep' fromTypeRep :: TypeRep -> ConcreteTypeRep fromTypeRep = CTR -- show as a normal TypeRep instance Show ConcreteTypeRep where showsPrec i = showsPrec i . unCTR -- | This instance is guaranteed to be consistent for a single run of the program, but not for multiple runs. instance Hashable ConcreteTypeRep where #if MIN_VERSION_base(4,8,0) hashWithSalt salt (CTR (TypeRep (Fingerprint w1 w2) _ _ _)) = salt `hashWithSalt` w1 `hashWithSalt` w2 #else hashWithSalt salt (CTR (TypeRep (Fingerprint w1 w2) _ _)) = salt `hashWithSalt` w1 `hashWithSalt` w2 #endif ------------- serialization: this uses Gökhan San's construction, from ---- http://www.mail-archive.com/haskell-cafe@haskell.org/msg41134.html toTyConRep :: TyCon -> TyConRep fromTyConRep :: TyConRep -> TyCon type TyConRep = (String, String, String) toTyConRep tc = (tyConPackage tc, tyConModule tc, tyConName tc) fromTyConRep (pack, mod', name) = mkTyCon3 pack mod' name newtype SerialRep = SR (TyConRep, [SerialRep]) deriving(Binary) toSerial :: ConcreteTypeRep -> SerialRep toSerial (CTR t) = case splitTyConApp t of (con, args) -> SR (toTyConRep con, map (toSerial . CTR) args) fromSerial :: SerialRep -> ConcreteTypeRep fromSerial (SR (con, args)) = CTR $ mkTyConApp (fromTyConRep con) (map (unCTR . fromSerial) args) instance Binary ConcreteTypeRep where put = put . toSerial get = fromSerial <$> get dynamic-state-0.2.2.0/src/Data/DynamicState/0000755000000000000000000000000012702027741016630 5ustar0000000000000000dynamic-state-0.2.2.0/src/Data/DynamicState/Serializable.hs0000644000000000000000000000621212702027741021573 0ustar0000000000000000{-# LANGUAGE ScopedTypeVariables #-} {-# LANGUAGE ExistentialQuantification #-} {-# LANGUAGE DeriveDataTypeable #-} {-# LANGUAGE TupleSections #-} {-# LANGUAGE CPP #-} {-# OPTIONS_HADDOCK show-extensions #-} -- | -- Module : Data.DynamicState.Serializable -- License : GPL2 -- Maintainer : zcarterc@gmail.com -- Stability : experimental -- Portability : portable -- -- This module is HashMap ConcreteTypeRep Dynamic with a twist. The Dynamic -- used can also be ByteString, to make repeated -- reserialization cheap. -- A user-provided State-like is used to store this. module Data.DynamicState.Serializable ( DynamicState(..), getDyn, putDyn ) where import Data.Binary import Data.HashMap.Strict as M import Data.ConcreteTypeRep import Data.Typeable import Data.ByteString.Lazy(ByteString) import Control.Applicative import Data.Monoid import Control.Monad -- | A Dynamic value, potentially stored serialized data Dynamic = forall a. (Typeable a, Binary a) => Dynamic !a | Serial !ByteString -- | Try to extract a value from the 'Dynamic', returning True if it was decoded from a 'Serial' fromDynamic :: forall a. (Typeable a, Binary a) => Dynamic -> Maybe (a,Bool) fromDynamic (Dynamic b) = (,False) <$> cast b #if __GLASGOW_HASKELL__ < 708 fromDynamic (Serial bs) = (,True) <$> (Just $ decode bs) #else fromDynamic (Serial bs) = let b = either (const Nothing) (\(_,_,a) -> Just a) $ decodeOrFail bs in (,True) <$> b #endif instance Binary Dynamic where put = put . toSerialRep where toSerialRep (Dynamic a) = encode a toSerialRep (Serial bs) = bs get = Serial <$> get -- | An extensible record, indexed by type, using state to cache deserializtion newtype DynamicState = DynamicState { unDynamicState :: M.HashMap ConcreteTypeRep Dynamic } deriving (Typeable) instance Monoid DynamicState where mappend (DynamicState a) (DynamicState b) = DynamicState (mappend a b) mempty = DynamicState mempty -- | Get a value, inside a State-like monad specified by the first two functions getDyn :: forall m a. (Typeable a, Binary a, Monad m) => m DynamicState -> (DynamicState -> m ()) -> m (Maybe a) getDyn get' put' = do let ty = cTypeOf (undefined::a) dvs <- liftM unDynamicState get' case M.lookup ty dvs >>= fromDynamic of Just (val,new) -> (when new $ put' $ DynamicState $ M.insert ty (Dynamic val) dvs) >> return (Just val) Nothing -> return Nothing -- | Set a value, inside a State-like monad specified by the first two functions putDyn :: forall m a. (Typeable a, Binary a, Monad m) => m DynamicState -> (DynamicState -> m ()) -> a -> m () putDyn get' put' v = do dvs <- liftM unDynamicState get' put' $ DynamicState (M.insert (cTypeOf (undefined :: a)) (Dynamic v) dvs) instance Binary DynamicState where put (DynamicState ds) = put (M.toList ds) get = DynamicState . M.fromList <$> get -- TODO: since a 'DynamicState' is now serialisable, it could potentially -- exist for a long time (days/months?). No operations are provided to remove -- entries. If these start accumulating a lot of junk, -- it may be necessary to prune them (perhaps keep track of access date and -- remove the ones more than a month old?).