diff --git a/ChangeLog.md b/ChangeLog.md new file mode 100644 --- /dev/null +++ b/ChangeLog.md @@ -0,0 +1,5 @@ +# Revision history for classy-effects + +## 0.1.0.0 -- 2023-09-18 + +* Initial public release. diff --git a/LICENSE b/LICENSE new file mode 100644 --- /dev/null +++ b/LICENSE @@ -0,0 +1,373 @@ +Mozilla Public License Version 2.0 +================================== + +1. Definitions +-------------- + +1.1. "Contributor" + means each individual or legal entity that creates, contributes to + the creation of, or owns Covered Software. + +1.2. "Contributor Version" + means the combination of the Contributions of others (if any) used + by a Contributor and that particular Contributor's Contribution. + +1.3. "Contribution" + means Covered Software of a particular Contributor. + +1.4. "Covered Software" + means Source Code Form to which the initial Contributor has attached + the notice in Exhibit A, the Executable Form of such Source Code + Form, and Modifications of such Source Code Form, in each case + including portions thereof. + +1.5. "Incompatible With Secondary Licenses" + means + + (a) that the initial Contributor has attached the notice described + in Exhibit B to the Covered Software; or + + (b) that the Covered Software was made available under the terms of + version 1.1 or earlier of the License, but not also under the + terms of a Secondary License. + +1.6. "Executable Form" + means any form of the work other than Source Code Form. + +1.7. "Larger Work" + means a work that combines Covered Software with other material, in + a separate file or files, that is not Covered Software. + +1.8. "License" + means this document. + +1.9. "Licensable" + means having the right to grant, to the maximum extent possible, + whether at the time of the initial grant or subsequently, any and + all of the rights conveyed by this License. + +1.10. "Modifications" + means any of the following: + + (a) any file in Source Code Form that results from an addition to, + deletion from, or modification of the contents of Covered + Software; or + + (b) any new file in Source Code Form that contains any Covered + Software. + +1.11. "Patent Claims" of a Contributor + means any patent claim(s), including without limitation, method, + process, and apparatus claims, in any patent Licensable by such + Contributor that would be infringed, but for the grant of the + License, by the making, using, selling, offering for sale, having + made, import, or transfer of either its Contributions or its + Contributor Version. + +1.12. "Secondary License" + means either the GNU General Public License, Version 2.0, the GNU + Lesser General Public License, Version 2.1, the GNU Affero General + Public License, Version 3.0, or any later versions of those + licenses. + +1.13. "Source Code Form" + means the form of the work preferred for making modifications. + +1.14. "You" (or "Your") + means an individual or a legal entity exercising rights under this + License. For legal entities, "You" includes any entity that + controls, is controlled by, or is under common control with You. For + purposes of this definition, "control" means (a) the power, direct + or indirect, to cause the direction or management of such entity, + whether by contract or otherwise, or (b) ownership of more than + fifty percent (50%) of the outstanding shares or beneficial + ownership of such entity. + +2. License Grants and Conditions +-------------------------------- + +2.1. Grants + +Each Contributor hereby grants You a world-wide, royalty-free, +non-exclusive license: + +(a) under intellectual property rights (other than patent or trademark) + Licensable by such Contributor to use, reproduce, make available, + modify, display, perform, distribute, and otherwise exploit its + Contributions, either on an unmodified basis, with Modifications, or + as part of a Larger Work; and + +(b) under Patent Claims of such Contributor to make, use, sell, offer + for sale, have made, import, and otherwise transfer either its + Contributions or its Contributor Version. + +2.2. Effective Date + +The licenses granted in Section 2.1 with respect to any Contribution +become effective for each Contribution on the date the Contributor first +distributes such Contribution. + +2.3. Limitations on Grant Scope + +The licenses granted in this Section 2 are the only rights granted under +this License. No additional rights or licenses will be implied from the +distribution or licensing of Covered Software under this License. +Notwithstanding Section 2.1(b) above, no patent license is granted by a +Contributor: + +(a) for any code that a Contributor has removed from Covered Software; + or + +(b) for infringements caused by: (i) Your and any other third party's + modifications of Covered Software, or (ii) the combination of its + Contributions with other software (except as part of its Contributor + Version); or + +(c) under Patent Claims infringed by Covered Software in the absence of + its Contributions. + +This License does not grant any rights in the trademarks, service marks, +or logos of any Contributor (except as may be necessary to comply with +the notice requirements in Section 3.4). + +2.4. Subsequent Licenses + +No Contributor makes additional grants as a result of Your choice to +distribute the Covered Software under a subsequent version of this +License (see Section 10.2) or under the terms of a Secondary License (if +permitted under the terms of Section 3.3). + +2.5. Representation + +Each Contributor represents that the Contributor believes its +Contributions are its original creation(s) or it has sufficient rights +to grant the rights to its Contributions conveyed by this License. + +2.6. Fair Use + +This License is not intended to limit any rights You have under +applicable copyright doctrines of fair use, fair dealing, or other +equivalents. + +2.7. Conditions + +Sections 3.1, 3.2, 3.3, and 3.4 are conditions of the licenses granted +in Section 2.1. + +3. Responsibilities +------------------- + +3.1. Distribution of Source Form + +All distribution of Covered Software in Source Code Form, including any +Modifications that You create or to which You contribute, must be under +the terms of this License. You must inform recipients that the Source +Code Form of the Covered Software is governed by the terms of this +License, and how they can obtain a copy of this License. You may not +attempt to alter or restrict the recipients' rights in the Source Code +Form. + +3.2. Distribution of Executable Form + +If You distribute Covered Software in Executable Form then: + +(a) such Covered Software must also be made available in Source Code + Form, as described in Section 3.1, and You must inform recipients of + the Executable Form how they can obtain a copy of such Source Code + Form by reasonable means in a timely manner, at a charge no more + than the cost of distribution to the recipient; and + +(b) You may distribute such Executable Form under the terms of this + License, or sublicense it under different terms, provided that the + license for the Executable Form does not attempt to limit or alter + the recipients' rights in the Source Code Form under this License. + +3.3. Distribution of a Larger Work + +You may create and distribute a Larger Work under terms of Your choice, +provided that You also comply with the requirements of this License for +the Covered Software. If the Larger Work is a combination of Covered +Software with a work governed by one or more Secondary Licenses, and the +Covered Software is not Incompatible With Secondary Licenses, this +License permits You to additionally distribute such Covered Software +under the terms of such Secondary License(s), so that the recipient of +the Larger Work may, at their option, further distribute the Covered +Software under the terms of either this License or such Secondary +License(s). + +3.4. Notices + +You may not remove or alter the substance of any license notices +(including copyright notices, patent notices, disclaimers of warranty, +or limitations of liability) contained within the Source Code Form of +the Covered Software, except that You may alter any license notices to +the extent required to remedy known factual inaccuracies. + +3.5. Application of Additional Terms + +You may choose to offer, and to charge a fee for, warranty, support, +indemnity or liability obligations to one or more recipients of Covered +Software. However, You may do so only on Your own behalf, and not on +behalf of any Contributor. You must make it absolutely clear that any +such warranty, support, indemnity, or liability obligation is offered by +You alone, and You hereby agree to indemnify every Contributor for any +liability incurred by such Contributor as a result of warranty, support, +indemnity or liability terms You offer. You may include additional +disclaimers of warranty and limitations of liability specific to any +jurisdiction. + +4. Inability to Comply Due to Statute or Regulation +--------------------------------------------------- + +If it is impossible for You to comply with any of the terms of this +License with respect to some or all of the Covered Software due to +statute, judicial order, or regulation then You must: (a) comply with +the terms of this License to the maximum extent possible; and (b) +describe the limitations and the code they affect. Such description must +be placed in a text file included with all distributions of the Covered +Software under this License. Except to the extent prohibited by statute +or regulation, such description must be sufficiently detailed for a +recipient of ordinary skill to be able to understand it. + +5. Termination +-------------- + +5.1. The rights granted under this License will terminate automatically +if You fail to comply with any of its terms. However, if You become +compliant, then the rights granted under this License from a particular +Contributor are reinstated (a) provisionally, unless and until such +Contributor explicitly and finally terminates Your grants, and (b) on an +ongoing basis, if such Contributor fails to notify You of the +non-compliance by some reasonable means prior to 60 days after You have +come back into compliance. Moreover, Your grants from a particular +Contributor are reinstated on an ongoing basis if such Contributor +notifies You of the non-compliance by some reasonable means, this is the +first time You have received notice of non-compliance with this License +from such Contributor, and You become compliant prior to 30 days after +Your receipt of the notice. + +5.2. If You initiate litigation against any entity by asserting a patent +infringement claim (excluding declaratory judgment actions, +counter-claims, and cross-claims) alleging that a Contributor Version +directly or indirectly infringes any patent, then the rights granted to +You by any and all Contributors for the Covered Software under Section +2.1 of this License shall terminate. + +5.3. In the event of termination under Sections 5.1 or 5.2 above, all +end user license agreements (excluding distributors and resellers) which +have been validly granted by You or Your distributors under this License +prior to termination shall survive termination. + +************************************************************************ +* * +* 6. Disclaimer of Warranty * +* ------------------------- * +* * +* Covered Software is provided under this License on an "as is" * +* basis, without warranty of any kind, either expressed, implied, or * +* statutory, including, without limitation, warranties that the * +* Covered Software is free of defects, merchantable, fit for a * +* particular purpose or non-infringing. The entire risk as to the * +* quality and performance of the Covered Software is with You. * +* Should any Covered Software prove defective in any respect, You * +* (not any Contributor) assume the cost of any necessary servicing, * +* repair, or correction. This disclaimer of warranty constitutes an * +* essential part of this License. No use of any Covered Software is * +* authorized under this License except under this disclaimer. * +* * +************************************************************************ + +************************************************************************ +* * +* 7. Limitation of Liability * +* -------------------------- * +* * +* Under no circumstances and under no legal theory, whether tort * +* (including negligence), contract, or otherwise, shall any * +* Contributor, or anyone who distributes Covered Software as * +* permitted above, be liable to You for any direct, indirect, * +* special, incidental, or consequential damages of any character * +* including, without limitation, damages for lost profits, loss of * +* goodwill, work stoppage, computer failure or malfunction, or any * +* and all other commercial damages or losses, even if such party * +* shall have been informed of the possibility of such damages. This * +* limitation of liability shall not apply to liability for death or * +* personal injury resulting from such party's negligence to the * +* extent applicable law prohibits such limitation. Some * +* jurisdictions do not allow the exclusion or limitation of * +* incidental or consequential damages, so this exclusion and * +* limitation may not apply to You. * +* * +************************************************************************ + +8. Litigation +------------- + +Any litigation relating to this License may be brought only in the +courts of a jurisdiction where the defendant maintains its principal +place of business and such litigation shall be governed by laws of that +jurisdiction, without reference to its conflict-of-law provisions. +Nothing in this Section shall prevent a party's ability to bring +cross-claims or counter-claims. + +9. Miscellaneous +---------------- + +This License represents the complete agreement concerning the subject +matter hereof. If any provision of this License is held to be +unenforceable, such provision shall be reformed only to the extent +necessary to make it enforceable. Any law or regulation which provides +that the language of a contract shall be construed against the drafter +shall not be used to construe this License against a Contributor. + +10. Versions of the License +--------------------------- + +10.1. New Versions + +Mozilla Foundation is the license steward. Except as provided in Section +10.3, no one other than the license steward has the right to modify or +publish new versions of this License. Each version will be given a +distinguishing version number. + +10.2. Effect of New Versions + +You may distribute the Covered Software under the terms of the version +of the License under which You originally received the Covered Software, +or under the terms of any subsequent version published by the license +steward. + +10.3. Modified Versions + +If you create software not governed by this License, and you want to +create a new license for such software, you may create and use a +modified version of this License if you rename the license and remove +any references to the name of the license steward (except to note that +such modified license differs from this License). + +10.4. Distributing Source Code Form that is Incompatible With Secondary +Licenses + +If You choose to distribute Source Code Form that is Incompatible With +Secondary Licenses under the terms of this version of the License, the +notice described in Exhibit B of this License must be attached. + +Exhibit A - Source Code Form License Notice +------------------------------------------- + + This Source Code Form is subject to the terms of the Mozilla Public + License, v. 2.0. If a copy of the MPL was not distributed with this + file, You can obtain one at https://mozilla.org/MPL/2.0/. + +If it is not possible or desirable to put the notice in a particular +file, then You may include the notice in a location (such as a LICENSE +file in a relevant directory) where a recipient would be likely to look +for such a notice. + +You may add additional accurate notices of copyright ownership. + +Exhibit B - "Incompatible With Secondary Licenses" Notice +--------------------------------------------------------- + + This Source Code Form is "Incompatible With Secondary Licenses", as + defined by the Mozilla Public License, v. 2.0. diff --git a/NOTICE b/NOTICE new file mode 100644 --- /dev/null +++ b/NOTICE @@ -0,0 +1,7 @@ +NOTICE +====== + +Unless explicitly stated otherwise, all Source Code Forms +(recursively, including under subdirectories) contained in the directory +where this NOTICE file is located are subject to the terms of the +Mozilla Public License, v. 2.0. diff --git a/README.md b/README.md new file mode 100644 --- /dev/null +++ b/README.md @@ -0,0 +1,25 @@ +# classy-effects + +This repository is for **CEPs** and its associated Haskell library. + +CEPs (Classy-Effects Protocols) are a collection of protocols for expressing and defining effects in Haskell, aimed at the fist objective in the [Sayo Project](https://github.com/sayo-hs): + +> Exploring ways to improve interoperability among the myriad Haskell effect system libraries + +For more details, please refer to [CEPs/README.md](https://github.com/sayo-hs/classy-effects/blob/master/CEPs/README.md). + +## Background +In Haskell, there are numerous libraries to realize an effect system. The issue here is interoperability between these libraries. For instance, the [Reader effect in `fused-effects`](https://hackage.haskell.org/package/fused-effects-1.1.2.2/docs/Control-Effect-Reader.html#t:Reader) and the [Reader effect in `polysemy`](https://hackage.haskell.org/package/polysemy-1.9.1.1/docs/Polysemy-Reader.html) have completely identical definitions. If we could extract and define effects purely as interfaces, eliminating this redundancy in effect definitions, then an effectful program could be handled by both effect system library A and effect system library B. The specific mechanisms for handling effects vary from one library to another, and unifying them isn't the goal. We're specifically looking to unify the overlapping and common definitions of effects as interfaces. + +Based on this idea, CEPs (classy-effects protocols) were developed. CEPs propose a convention (protocol) for unified effect definitions in Haskell. It's expected that effects defined in accordance with CEPs will be usable across various effect systems and backends. + +## Encoding of Effect +First, for the representation of effects, there is the GADTs encoding typical in Extensible Effects and the type-class encoding typical in the monad transformer approach. In principle, if the type class representing the effect is decided, GADTs can be automatically generated, and the reverse is probably also possible. There's a kind of symmetry here. However, type classes have the advantage of expressing inclusion relationships of effects naturally by specifying superclasses. From this perspective, CEPs primarily adopt type class representation for effects. Moreover, a mechanism has been implemented to derive GADTs from type classes[^1], and from GADTs and the type classes that cast them to monads ([`SendIns`](https://hackage.haskell.org/package/classy-effects-base-0.1.0.0/docs/Control-Effect-Class.html#t:SendIns), [`SendSig`](https://hackage.haskell.org/package/classy-effects-base-0.1.0.0/docs/Control-Effect-Class.html#t:SendSig)), to automatically derive instances of the effect's type class ([`classy-effects-th`](https://hackage.haskell.org/package/classy-effects-th)). This allows compliance with CEPs automatically by just writing the type class that represents the effect. + +[^1]: In the future, we might also consider implementing the derivation of type classes from GADTs. + +## Examples +Examples of using classy-effects combined with the Heftia effect handler backend can be found [here](https://github.com/sayo-hs/heftia/blob/master/docs/examples/01%20First-order.md). + +## Your contributions are welcome! +Please see [CONTRIBUTING.md](https://github.com/sayo-hs/classy-effects/blob/master/CONTRIBUTING.md). diff --git a/classy-effects.cabal b/classy-effects.cabal new file mode 100644 --- /dev/null +++ b/classy-effects.cabal @@ -0,0 +1,122 @@ +cabal-version: 2.4 +name: classy-effects +version: 0.1.0.0 + +-- A short (one-line) description of the package. +synopsis: An interface for a handler-independent, typeclass-based effect system. + +-- A longer description of the package. +description: + This library provides definitions for CEPs (classy-effects protocols) to standardize and unify + the definition of effects in Haskell in a backend-library-agnostic manner. It also includes + several standard effect definitions defined in compliance with CEPs, and Template Haskell + functions to automatically make type classes conform to CEPs as effect classes. + + Please refer + to [CEPs](https://github.com/sayo-hs/classy-effects/blob/master/CEPs/README.md) for details. + + The Template Haskell functions are re-exported + from the [classy-effects-th](https://hackage.haskell.org/package/classy-effects-th) package, + while the fundamental definitions are re-exported + from the [classy-effects-base](https://hackage.haskell.org/package/classy-effects-base) + package. + +-- A URL where users can report bugs. +bug-reports: https://github.com/sayo-hs/classy-effects + +-- The license under which the package is released. +license: MPL-2.0 +license-file: LICENSE +author: Yamada Ryo +maintainer: Yamada Ryo + +-- A copyright notice. +copyright: 2023 Yamada Ryo +category: Control, Effect + +extra-source-files: + ChangeLog.md + NOTICE + README.md + +tested-with: + GHC == 9.2.8 + +source-repository head + type: git + location: https://github.com/sayo-hs/classy-effects + tag: v0.1.0 + subdir: classy-effects + +library + exposed-modules: + Control.Effect.Class.Reader + Control.Effect.Class.Writer + Control.Effect.Class.State + Control.Effect.Class.Except + Control.Effect.Class.Accum + Control.Effect.Class.Coroutine + Control.Effect.Class.Input + Control.Effect.Class.Output + Control.Effect.Class.Provider + + reexported-modules: + Control.Effect.Class, + Control.Effect.Class.Machinery.HFunctor, + Control.Effect.Class.Machinery.TH, + Data.Effect.Class.TH, + Data.Effect.Class.TH.HFunctor, + + -- Modules included in this executable, other than Main. + other-modules: + Prelude + + -- LANGUAGE extensions used by modules in this package. + -- other-extensions: + build-depends: + base ^>= 4.16.4.0, + classy-effects-base ^>= 0.1, + classy-effects-th ^>= 0.1, + + hs-source-dirs: src + ghc-options: -Wall + default-language: GHC2021 + + default-extensions: + LambdaCase, + DerivingStrategies, + DataKinds, + TypeFamilies, + BlockArguments, + FunctionalDependencies, + RecordWildCards, + DefaultSignatures, + PatternSynonyms, + TemplateHaskell, + PartialTypeSignatures + +test-suite test + main-is: Driver.hs + hs-source-dirs: test + build-depends: + classy-effects, + base, + tasty ^>= 1.4, + tasty-hunit ^>= 0.10, + + type: exitcode-stdio-1.0 + + build-tool-depends: + tasty-discover:tasty-discover + + default-language: GHC2021 + + default-extensions: + LambdaCase, + DerivingStrategies, + DataKinds, + TypeFamilies, + BlockArguments, + FunctionalDependencies, + RecordWildCards, + DefaultSignatures diff --git a/src/Control/Effect/Class/Accum.hs b/src/Control/Effect/Class/Accum.hs new file mode 100644 --- /dev/null +++ b/src/Control/Effect/Class/Accum.hs @@ -0,0 +1,20 @@ +{-# LANGUAGE UndecidableInstances #-} + +-- This Source Code Form is subject to the terms of the Mozilla Public +-- License, v. 2.0. If a copy of the MPL was not distributed with this +-- file, You can obtain one at https://mozilla.org/MPL/2.0/. + +{- | +Copyright : (c) 2023 Yamada Ryo +License : MPL-2.0 (see the file LICENSE) +Maintainer : ymdfield@outlook.jp +Stability : experimental +Portability : portable +-} +module Control.Effect.Class.Accum where + +class Monoid w => Accum w f where + add :: w -> f () + look :: f w + +makeEffectF ''Accum diff --git a/src/Control/Effect/Class/Coroutine.hs b/src/Control/Effect/Class/Coroutine.hs new file mode 100644 --- /dev/null +++ b/src/Control/Effect/Class/Coroutine.hs @@ -0,0 +1,24 @@ +{-# LANGUAGE UndecidableInstances #-} + +-- This Source Code Form is subject to the terms of the Mozilla Public +-- License, v. 2.0. If a copy of the MPL was not distributed with this +-- file, You can obtain one at https://mozilla.org/MPL/2.0/. + +{- | +Copyright : (c) 2016 Allele Dev; 2017 Ixperta Solutions s.r.o.; 2017 Alexis King + (c) 2023 Yamada Ryo +License : MPL-2.0 (see the file LICENSE) +Maintainer : ymdfield@outlook.jp +Stability : experimental +Portability : portable + +This module provides the t`Coroutine` effect, comes +from [@Control.Monad.Freer.Coroutine@](https://hackage.haskell.org/package/freer-simple-1.2.1.2/docs/Control-Monad-Freer-Coroutine.html) +in the @freer-simple@ package. +-} +module Control.Effect.Class.Coroutine where + +class Coroutine a b f where + yield :: a -> (b -> c) -> f c + +makeEffectF ''Coroutine diff --git a/src/Control/Effect/Class/Except.hs b/src/Control/Effect/Class/Except.hs new file mode 100644 --- /dev/null +++ b/src/Control/Effect/Class/Except.hs @@ -0,0 +1,22 @@ +{-# LANGUAGE UndecidableInstances #-} + +-- This Source Code Form is subject to the terms of the Mozilla Public +-- License, v. 2.0. If a copy of the MPL was not distributed with this +-- file, You can obtain one at https://mozilla.org/MPL/2.0/. + +{- | +Copyright : (c) 2023 Yamada Ryo +License : MPL-2.0 (see the file LICENSE) +Maintainer : ymdfield@outlook.jp +Stability : experimental +Portability : portable +-} +module Control.Effect.Class.Except where + +class Throw e (f :: Type -> Type) where + throw :: e -> f a + +class Catch e f where + catch :: f a -> (e -> f a) -> f a + +makeEffect "Except" ''Throw ''Catch diff --git a/src/Control/Effect/Class/Input.hs b/src/Control/Effect/Class/Input.hs new file mode 100644 --- /dev/null +++ b/src/Control/Effect/Class/Input.hs @@ -0,0 +1,23 @@ +{-# LANGUAGE UndecidableInstances #-} + +-- This Source Code Form is subject to the terms of the Mozilla Public +-- License, v. 2.0. If a copy of the MPL was not distributed with this +-- file, You can obtain one at https://mozilla.org/MPL/2.0/. + +{- | +Copyright : (c) 2023 Yamada Ryo +License : MPL-2.0 (see the file LICENSE) +Maintainer : ymdfield@outlook.jp +Stability : experimental +Portability : portable + +This module provides the t`Input` effect, comes +from [@Polysemy.Input@](https://hackage.haskell.org/package/polysemy-1.9.1.1/docs/Polysemy-Input.html) +in the @polysemy@ package. +-} +module Control.Effect.Class.Input where + +class Input i (f :: Type -> Type) where + input :: f i + +makeEffectF ''Input diff --git a/src/Control/Effect/Class/Output.hs b/src/Control/Effect/Class/Output.hs new file mode 100644 --- /dev/null +++ b/src/Control/Effect/Class/Output.hs @@ -0,0 +1,23 @@ +{-# LANGUAGE UndecidableInstances #-} + +-- This Source Code Form is subject to the terms of the Mozilla Public +-- License, v. 2.0. If a copy of the MPL was not distributed with this +-- file, You can obtain one at https://mozilla.org/MPL/2.0/. + +{- | +Copyright : (c) 2023 Yamada Ryo +License : MPL-2.0 (see the file LICENSE) +Maintainer : ymdfield@outlook.jp +Stability : experimental +Portability : portable + +This module provides the t`Output` effect, comes +from [@Polysemy.Output@](https://hackage.haskell.org/package/polysemy-1.9.1.1/docs/Polysemy-Output.html) +in the @polysemy@ package. +-} +module Control.Effect.Class.Output where + +class Output o f where + output :: o -> f () + +makeEffectF ''Output diff --git a/src/Control/Effect/Class/Provider.hs b/src/Control/Effect/Class/Provider.hs new file mode 100644 --- /dev/null +++ b/src/Control/Effect/Class/Provider.hs @@ -0,0 +1,69 @@ +{-# LANGUAGE UndecidableInstances #-} + +-- This Source Code Form is subject to the terms of the Mozilla Public +-- License, v. 2.0. If a copy of the MPL was not distributed with this +-- file, You can obtain one at https://mozilla.org/MPL/2.0/. + +{- | +Copyright : (c) 2023 Yamada Ryo +License : MPL-2.0 (see the file LICENSE) +Maintainer : ymdfield@outlook.jp +Stability : experimental +Portability : portable + +This module provides the `Provider` effect, comes +from [@Effectful.Provider@](https://hackage.haskell.org/package/effectful-core-2.3.0.0/docs/Effectful-Provider.html) +in the @effectful@ package. +-} +module Control.Effect.Class.Provider where + +import Control.Effect.Class ( + EffectDataHandler, + EffectsVia (EffectsVia), + SendSig, + runEffectsVia, + sendSig, + type (~>), + ) +import Control.Effect.Class.Machinery.HFunctor (HFunctor, hfmap) +import Data.Effect.Class.TH ( + makeSignature, + ) + +class Provider c e i g (f :: Type -> Type) where + provide :: i -> (forall h. (c h, e h) => (f ~> h) -> h a) -> f (g a) + +makeSignature ''Provider + +instance HFunctor (ProviderS c e i g) where + hfmap phi (Provide i f) = Provide i \l -> f $ l . phi + +instance + SendSig (ProviderS c e i g) f => + Provider c e i g (EffectsVia EffectDataHandler f) + where + {-# INLINE provide #-} + provide i f = + EffectsVia + . sendSig + . hfmap (runEffectsVia @EffectDataHandler) + $ Provide @c @e i f + +type MonadProvider = Provider Monad +type ApplicativeProvider = Provider Applicative + +mprovide :: + MonadProvider e i g f => + i -> + (forall h. (Monad h, e h) => (f ~> h) -> h a) -> + f (g a) +mprovide = provide +{-# INLINE mprovide #-} + +aprovide :: + ApplicativeProvider e i g f => + i -> + (forall h. (Applicative h, e h) => (f ~> h) -> h a) -> + f (g a) +aprovide = provide +{-# INLINE aprovide #-} diff --git a/src/Control/Effect/Class/Reader.hs b/src/Control/Effect/Class/Reader.hs new file mode 100644 --- /dev/null +++ b/src/Control/Effect/Class/Reader.hs @@ -0,0 +1,25 @@ +{-# LANGUAGE UndecidableInstances #-} + +-- This Source Code Form is subject to the terms of the Mozilla Public +-- License, v. 2.0. If a copy of the MPL was not distributed with this +-- file, You can obtain one at https://mozilla.org/MPL/2.0/. + +{- | +Copyright : (c) 2023 Yamada Ryo +License : MPL-2.0 (see the file LICENSE) +Maintainer : ymdfield@outlook.jp +Stability : experimental +Portability : portable +-} +module Control.Effect.Class.Reader where + +class Ask (r :: Type) f where + ask :: f r + +class Local r f where + local :: (r -> r) -> f a -> f a + +makeEffect "Reader" ''Ask ''Local + +asks :: (Ask r f, Functor f) => (r -> a) -> f a +asks f = f <$> ask diff --git a/src/Control/Effect/Class/State.hs b/src/Control/Effect/Class/State.hs new file mode 100644 --- /dev/null +++ b/src/Control/Effect/Class/State.hs @@ -0,0 +1,26 @@ +{-# LANGUAGE UndecidableInstances #-} + +-- This Source Code Form is subject to the terms of the Mozilla Public +-- License, v. 2.0. If a copy of the MPL was not distributed with this +-- file, You can obtain one at https://mozilla.org/MPL/2.0/. + +{- | +Copyright : (c) 2023 Yamada Ryo +License : MPL-2.0 (see the file LICENSE) +Maintainer : ymdfield@outlook.jp +Stability : experimental +Portability : portable +-} +module Control.Effect.Class.State where + +class State s f where + get :: f s + put :: s -> f () + +makeEffectF ''State + +gets :: (State s f, Functor f) => (s -> a) -> f a +gets f = f <$> get + +modify :: (State s m, Monad m) => (s -> s) -> m () +modify f = put . f =<< get diff --git a/src/Control/Effect/Class/Writer.hs b/src/Control/Effect/Class/Writer.hs new file mode 100644 --- /dev/null +++ b/src/Control/Effect/Class/Writer.hs @@ -0,0 +1,23 @@ +{-# LANGUAGE UndecidableInstances #-} + +-- This Source Code Form is subject to the terms of the Mozilla Public +-- License, v. 2.0. If a copy of the MPL was not distributed with this +-- file, You can obtain one at https://mozilla.org/MPL/2.0/. + +{- | +Copyright : (c) 2023 Yamada Ryo +License : MPL-2.0 (see the file LICENSE) +Maintainer : ymdfield@outlook.jp +Stability : experimental +Portability : portable +-} +module Control.Effect.Class.Writer where + +class Monoid w => Tell w f where + tell :: w -> f () + +class Monoid w => WriterH w f where + listen :: f a -> f (a, w) + censor :: (w -> w) -> f a -> f a + +makeEffect "Writer" ''Tell ''WriterH diff --git a/src/Prelude.hs b/src/Prelude.hs new file mode 100644 --- /dev/null +++ b/src/Prelude.hs @@ -0,0 +1,11 @@ +{-# LANGUAGE PackageImports #-} + +-- This Source Code Form is subject to the terms of the Mozilla Public +-- License, v. 2.0. If a copy of the MPL was not distributed with this +-- file, You can obtain one at https://mozilla.org/MPL/2.0/. + +module Prelude (module Prelude, makeEffect, makeEffectF, makeEffectH, Type) where + +import Control.Effect.Class.Machinery.TH (makeEffect, makeEffectF, makeEffectH) +import Data.Kind (Type) +import "base" Prelude diff --git a/test/Driver.hs b/test/Driver.hs new file mode 100644 --- /dev/null +++ b/test/Driver.hs @@ -0,0 +1,5 @@ +{-# OPTIONS_GHC -F -pgmF tasty-discover #-} + +-- This Source Code Form is subject to the terms of the Mozilla Public +-- License, v. 2.0. If a copy of the MPL was not distributed with this +-- file, You can obtain one at https://mozilla.org/MPL/2.0/.