diff --git a/ChangeLog.adoc b/ChangeLog.adoc
new file mode 100644
--- /dev/null
+++ b/ChangeLog.adoc
@@ -0,0 +1,3 @@
+= Changelog for polysemy-scoped-fs
+
+== Unreleased changes
diff --git a/ChangeLog.md b/ChangeLog.md
new file mode 100644
--- /dev/null
+++ b/ChangeLog.md
@@ -0,0 +1,3 @@
+# Changelog for polysemy-scoped-fs
+
+## Unreleased changes
diff --git a/LICENSE b/LICENSE
new file mode 100644
--- /dev/null
+++ b/LICENSE
@@ -0,0 +1,682 @@
+Copyright (C) 2022 Hisaket VioletRed
+
+This package is mainly licensed under 'AGPL-3.0-or-later'. However,
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+under 'AGPL-3.0-or-later AND BSD-...'. Please see the header comments
+in these files for the details. These files also include the copyright
+notice, the conditions, and the disclaimer related to the BSD license.
+
+* src/Polysemy/Scoped/Path.hs
+* src/Polysemy/Scoped/Path/Internal.hs
+* src/Polysemy/FS/Scoped/Internal.hs
+
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+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.
+
+ 16. Limitation of Liability.
+
+ IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
+WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS
+THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY
+GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE
+USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF
+DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD
+PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS),
+EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF
+SUCH DAMAGES.
+
+ 17. Interpretation of Sections 15 and 16.
+
+ If the disclaimer of warranty and limitation of liability provided
+above cannot be given local legal effect according to their terms,
+reviewing courts shall apply local law that most closely approximates
+an absolute waiver of all civil liability in connection with the
+Program, unless a warranty or assumption of liability accompanies a
+copy of the Program in return for a fee.
+
+ END OF TERMS AND CONDITIONS
+
+ How to Apply These Terms to Your New Programs
+
+ If you develop a new program, and you want it to be of the greatest
+possible use to the public, the best way to achieve this is to make it
+free software which everyone can redistribute and change under these terms.
+
+ To do so, attach the following notices to the program. It is safest
+to attach them to the start of each source file to most effectively
+state 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 Affero General Public License as published by
+ the Free Software Foundation, either version 3 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 Affero General Public License for more details.
+
+ You should have received a copy of the GNU Affero General Public License
+ along with this program. If not, see .
+
+Also add information on how to contact you by electronic and paper mail.
+
+ If your software can interact with users remotely through a computer
+network, you should also make sure that it provides a way for users to
+get its source. For example, if your program is a web application, its
+interface could display a "Source" link that leads users to an archive
+of the code. There are many ways you could offer source, and different
+solutions will be better for different programs; see section 13 for the
+specific requirements.
+
+ You should also get your employer (if you work as a programmer) or school,
+if any, to sign a "copyright disclaimer" for the program, if necessary.
+For more information on this, and how to apply and follow the GNU AGPL, see
+.
diff --git a/README.adoc b/README.adoc
new file mode 100644
--- /dev/null
+++ b/README.adoc
@@ -0,0 +1,81 @@
+= polysemy-scoped-fs
+:source-highlighter: highlight.js
+:highlightjs-languages: haskell
+
+This package provides well-typed (scoped) filesystem operation effects.
+This is based on the idea and codes of https://www.tweag.io/blog/2022-01-05-polysemy-scoped/[Scoped Effect Resources for Polysemy] by Torsten Schmits.
+
+== Example
+
+We assume that the language extensions related to polysemy and polysemy-plugin are enabled.
+cf. https://hackage.haskell.org/package/polysemy-1.7.1.0#readme
+
+[source,haskell]
+----
+{-# LANGUAGE OverloadedStrings #-}
+
+import qualified Polysemy.SequentialAccess as SA
+import Polysemy (runFinal, embedToFinal, embed)
+import Polysemy.Resource (resourceToIOFinal)
+import Polysemy.Path
+import Polysemy.FS.Scoped (scopedFile, AccessMode(RwAccess, ReadAccess))
+import Polysemy.FS.Scoped.Text (rwAccessToIO, readAccessToIO)
+
+writeFoobar :: IO ()
+writeFoobar =
+ runFinal $ embedToFinal $ resourceToIOFinal $ rwAccessToIO $ readAccessToIO $ do
+ -- Open the file '/tmp/polysemy-scoped-fs-test' with read & write access mode.
+ scopedFile @RwAccess [absfile|/tmp/polysemy-scoped-fs-test|] $ do
+ SA.extend "This text will be deleted."
+ SA.resize SA.NullSize -- Clear the file.
+ SA.extend "foo" -- Append the text to the file.
+ SA.extend "bar"
+ SA.seek SA.TOF -- Seek to the top of the file.
+ embed . print =<< SA.read SA.ToEnd
+
+ -- Open the file with read only access mode.
+ scopedFile @ReadAccess [absfile|/tmp/polysemy-scoped-fs-test|] $ do
+ embed . print =<< SA.read SA.ToEnd
+
+ -- SA.extend "baz"
+ {- We get the following type error *before runtime* ! :
+ • Unhandled effect 'SA.Extend [Char]'
+ Probable fix:
+ add an interpretation for 'SA.Extend [Char]'
+ • In a stmt of a 'do' block: SA.extend "baz"
+ In the third argument of ‘scopedFile’, namely
+ ‘do embed . print =<< SA.read SA.ToEnd
+ SA.extend "baz"’
+ In a stmt of a 'do' block:
+ scopedFile
+ @ReadAccess
+ (Path.Internal.Path "/tmp/polysemy-scoped-fs-test" ::
+ Path Abs File)
+ do embed . print =<< SA.read SA.ToEnd
+ SA.extend "baz"
+ -}
+
+-- >>> writeFoobar
+-- "foobar"
+-- "foobar"
+----
+
+== License
+
+This package is mainly licensed under 'AGPL-3.0-or-later'. However,
+only the below files partially contain source codes that are licensed
+under 'AGPL-3.0-or-later AND BSD-...'. Please see the header comments
+in these files for the details. These files also include the copyright
+notice, the conditions, and the disclaimer related to the BSD license.
+
+* src/Polysemy/Scoped/Path.hs
+* src/Polysemy/Scoped/Path/Internal.hs
+* src/Polysemy/FS/Scoped/Internal.hs
+
+=== Submission of Contributions
+
+Unless You explicitly state otherwise, any Contribution intentionally
+submitted for inclusion in the Work by You to the Licensor shall be
+under the terms and conditions of AGPL-3.0-or-later, without any
+additional terms or conditions; where Contribution, Work, You, and
+Licensor are as defined in the Apache-2.0 license.
diff --git a/README.md b/README.md
new file mode 100644
--- /dev/null
+++ b/README.md
@@ -0,0 +1,83 @@
+# polysemy-scoped-fs
+
+This package provides well-typed (scoped) filesystem operation effects.
+This is based on the idea and codes of [Scoped Effect Resources for
+Polysemy](https://www.tweag.io/blog/2022-01-05-polysemy-scoped/) by
+Torsten Schmits.
+
+## Example
+
+We assume that the language extensions related to polysemy and
+polysemy-plugin are enabled. cf.
+
+
+``` haskell
+{-# LANGUAGE OverloadedStrings #-}
+
+import qualified Polysemy.SequentialAccess as SA
+import Polysemy (runFinal, embedToFinal, embed)
+import Polysemy.Resource (resourceToIOFinal)
+import Polysemy.Path
+import Polysemy.FS.Scoped (scopedFile, AccessMode(RwAccess, ReadAccess))
+import Polysemy.FS.Scoped.Text (rwAccessToIO, readAccessToIO)
+
+writeFoobar :: IO ()
+writeFoobar =
+ runFinal $ embedToFinal $ resourceToIOFinal $ rwAccessToIO $ readAccessToIO $ do
+ -- Open the file '/tmp/polysemy-scoped-fs-test' with read & write access mode.
+ scopedFile @RwAccess [absfile|/tmp/polysemy-scoped-fs-test|] $ do
+ SA.extend "This text will be deleted."
+ SA.resize SA.NullSize -- Clear the file.
+ SA.extend "foo" -- Append the text to the file.
+ SA.extend "bar"
+ SA.seek SA.TOF -- Seek to the top of the file.
+ embed . print =<< SA.read SA.ToEnd
+
+ -- Open the file with read only access mode.
+ scopedFile @ReadAccess [absfile|/tmp/polysemy-scoped-fs-test|] $ do
+ embed . print =<< SA.read SA.ToEnd
+
+ -- SA.extend "baz"
+ {- We get the following type error *before runtime* ! :
+ • Unhandled effect 'SA.Extend [Char]'
+ Probable fix:
+ add an interpretation for 'SA.Extend [Char]'
+ • In a stmt of a 'do' block: SA.extend "baz"
+ In the third argument of ‘scopedFile’, namely
+ ‘do embed . print =<< SA.read SA.ToEnd
+ SA.extend "baz"’
+ In a stmt of a 'do' block:
+ scopedFile
+ @ReadAccess
+ (Path.Internal.Path "/tmp/polysemy-scoped-fs-test" ::
+ Path Abs File)
+ do embed . print =<< SA.read SA.ToEnd
+ SA.extend "baz"
+ -}
+
+-- >>> writeFoobar
+-- "foobar"
+-- "foobar"
+```
+
+## License
+
+This package is mainly licensed under 'AGPL-3.0-or-later'. However, only
+the below files partially contain source codes that are licensed under
+'AGPL-3.0-or-later AND BSD-…'. Please see the header comments in these
+files for the details. These files also include the copyright notice,
+the conditions, and the disclaimer related to the BSD license.
+
+- src/Polysemy/Scoped/Path.hs
+
+- src/Polysemy/Scoped/Path/Internal.hs
+
+- src/Polysemy/FS/Scoped/Internal.hs
+
+### Submission of Contributions
+
+Unless You explicitly state otherwise, any Contribution intentionally
+submitted for inclusion in the Work by You to the Licensor shall be
+under the terms and conditions of AGPL-3.0-or-later, without any
+additional terms or conditions; where Contribution, Work, You, and
+Licensor are as defined in the Apache-2.0 license.
diff --git a/Setup.hs b/Setup.hs
new file mode 100644
--- /dev/null
+++ b/Setup.hs
@@ -0,0 +1,2 @@
+import Distribution.Simple
+main = defaultMain
diff --git a/polysemy-scoped-fs.cabal b/polysemy-scoped-fs.cabal
new file mode 100644
--- /dev/null
+++ b/polysemy-scoped-fs.cabal
@@ -0,0 +1,125 @@
+cabal-version: 2.2
+
+-- This file has been generated from package.yaml by hpack version 0.34.4.
+--
+-- see: https://github.com/sol/hpack
+
+name: polysemy-scoped-fs
+version: 0.1.0.0
+synopsis: Well-typed filesystem operation effects.
+description: Please see the README on GitLab at
+category: Polysemy Filesystem
+homepage: https://gitlab.com/hisaket/polysemy-scoped-fs
+bug-reports: https://gitlab.com/hisaket/polysemy-scoped-fs/issues
+author: Hisaket VioletRed
+maintainer: hisaket@outlook.jp
+copyright: 2022 Hisaket VioletRed
+license: AGPL-3.0-or-later
+license-file: LICENSE
+build-type: Simple
+extra-source-files:
+ README.adoc
+ ChangeLog.adoc
+ README.md
+ ChangeLog.md
+
+source-repository head
+ type: git
+ location: https://gitlab.com/hisaket/polysemy-scoped-fs
+
+library
+ exposed-modules:
+ Polysemy.Env
+ Polysemy.FS.Scoped
+ Polysemy.FS.Scoped.ByteString
+ Polysemy.FS.Scoped.ByteString.Internal
+ Polysemy.FS.Scoped.Internal
+ Polysemy.FS.Scoped.Internal.MembersProof
+ Polysemy.FS.Scoped.Oneshot
+ Polysemy.FS.Scoped.Text
+ Polysemy.FS.Scoped.Text.Internal
+ Polysemy.Scoped.Path
+ Polysemy.Scoped.Path.Internal
+ Polysemy.Scoped.Path.Isolation
+ Polysemy.ScopedReader
+ Polysemy.SequentialAccess
+ Polysemy.SequentialAccess.ByteString
+ Polysemy.SequentialAccess.Text
+ other-modules:
+ Paths_polysemy_scoped_fs
+ hs-source-dirs:
+ src
+ default-extensions:
+ DataKinds
+ FlexibleContexts
+ GADTs
+ LambdaCase
+ PolyKinds
+ RankNTypes
+ ScopedTypeVariables
+ TypeApplications
+ TypeOperators
+ TypeFamilies
+ UnicodeSyntax
+ BlockArguments
+ TemplateHaskell
+ QuasiQuotes
+ ghc-options: -flate-specialise -fspecialise-aggressively -fplugin=Polysemy.Plugin -fwarn-incomplete-patterns
+ build-depends:
+ base >=4.7 && <5
+ , bytestring >=0.10.12 && <0.11
+ , directory >=1.3.6 && <1.4
+ , doctest ==0.17.*
+ , extra >=1.7.9 && <1.8
+ , path >=0.8.0 && <0.9
+ , polysemy >=1.7.1 && <1.8
+ , polysemy-fs >=0.1.0 && <0.2
+ , polysemy-path >=0.2.0 && <0.3
+ , polysemy-plugin >=0.4.3 && <0.5
+ , text >=1.2.4 && <1.3
+ default-language: Haskell2010
+ autogen-modules: Paths_polysemy_scoped_fs
+
+test-suite polysemy-scoped-fs-doctest
+ type: exitcode-stdio-1.0
+ main-is: test/doctests.hs
+ other-modules:
+ Paths_polysemy_scoped_fs
+ ghc-options: -threaded -rtsopts -with-rtsopts=-N
+ build-depends:
+ base >=4.7 && <5
+ , bytestring >=0.10.12 && <0.11
+ , directory >=1.3.6 && <1.4
+ , doctest ==0.17.*
+ , extra >=1.7.9 && <1.8
+ , path >=0.8.0 && <0.9
+ , polysemy >=1.7.1 && <1.8
+ , polysemy-fs >=0.1.0 && <0.2
+ , polysemy-path >=0.2.0 && <0.3
+ , polysemy-plugin >=0.4.3 && <0.5
+ , polysemy-scoped-fs
+ , text >=1.2.4 && <1.3
+ default-language: Haskell2010
+
+test-suite polysemy-scoped-fs-test
+ type: exitcode-stdio-1.0
+ main-is: Spec.hs
+ other-modules:
+ Paths_polysemy_scoped_fs
+ hs-source-dirs:
+ test
+ ghc-options: -threaded -rtsopts -with-rtsopts=-N
+ build-depends:
+ base >=4.7 && <5
+ , bytestring >=0.10.12 && <0.11
+ , directory >=1.3.6 && <1.4
+ , doctest ==0.17.*
+ , extra >=1.7.9 && <1.8
+ , path >=0.8.0 && <0.9
+ , polysemy >=1.7.1 && <1.8
+ , polysemy-fs >=0.1.0 && <0.2
+ , polysemy-path >=0.2.0 && <0.3
+ , polysemy-plugin >=0.4.3 && <0.5
+ , polysemy-scoped-fs
+ , text >=1.2.4 && <1.3
+ default-language: Haskell2010
diff --git a/src/Polysemy/Env.hs b/src/Polysemy/Env.hs
new file mode 100644
--- /dev/null
+++ b/src/Polysemy/Env.hs
@@ -0,0 +1,26 @@
+{-|
+Copyright : (c) Hisaket VioletRed, 2022
+License : AGPL-3.0-or-later
+Maintainer : hisaket@outlook.jp
+Stability : experimental
+-}
+
+module Polysemy.Env where
+
+import Polysemy ( Member, Sem, interpret, makeSem )
+import Polysemy.Input ( Input (Input) )
+
+-- | Variant of 'Input' effect that has no side effects.
+data Env i m a where
+ Env :: Env i m i
+makeSem ''Env
+
+{- |Transforms an 'Input' effect into an `Env` effect.
+ Note that "askToInput" of inverted version is not provided because an 'Env' effect is specialized version of an 'Input' effect.
+-}
+inputToEnv :: Member (Env i) r => Sem (Input i ': r) a -> Sem r a
+inputToEnv = interpret \Input -> env
+
+-- | Runs an 'Env' effect.
+runEnvConst :: i -> Sem (Env i ': r) a -> Sem r a
+runEnvConst i = interpret \Env -> pure i
diff --git a/src/Polysemy/FS/Scoped.hs b/src/Polysemy/FS/Scoped.hs
new file mode 100644
--- /dev/null
+++ b/src/Polysemy/FS/Scoped.hs
@@ -0,0 +1,108 @@
+{-|
+Copyright : (c) Hisaket VioletRed, 2022
+License : AGPL-3.0-or-later
+Maintainer : hisaket@outlook.jp
+Stability : experimental
+Portability : POSIX
+
+The behavior about file access mode conforms 'System.IO.IOMode' and 'System.IO.openFile'.
+-}
+
+{-# LANGUAGE MultiParamTypeClasses #-}
+{-# LANGUAGE FlexibleInstances #-}
+{-# LANGUAGE AllowAmbiguousTypes #-}
+{-# LANGUAGE UndecidableInstances #-}
+{-# OPTIONS_GHC -Wno-unrecognised-pragmas #-}
+{-# HLINT ignore "Use camelCase" #-}
+
+module Polysemy.FS.Scoped
+ ( module Polysemy.FS.Scoped
+ , ScopedFile
+ , sendBundle_
+ , runScopedFile
+ )
+ where
+
+import Polysemy.Path ( Path, File )
+import Polysemy.Bundle ( injBundle, Bundle )
+import Polysemy
+ ( Member
+ , Sem
+ , raise2Under
+ , raiseUnder
+ , subsume
+ , InterpretersFor
+ , rewrite
+ , transform
+ )
+import Polysemy.Scoped.Path ( ScopedP, scopedP )
+import Polysemy.FS.Scoped.Internal
+ ( ScopedFile (ScopedFile), sendBundle_, runScopedFile, unScopedFile )
+import Polysemy.Input ( Input )
+import Polysemy.Internal.Sing ( KnownList )
+import Polysemy.Internal.Kind ( Append )
+import Control.Category ((>>>))
+
+
+scopedFile
+ :: ∀accessMode format es b r handle a
+ . (Member (ScopedFile (Mode format accessMode) es b handle) r, KnownList es)
+ => Path b File -> Sem (Append es (Bundle es ': Input (Path b File) ': r)) a -> Sem r a
+scopedFile path = scopedFile_bundle path . sendBundle_
+
+scopedFile_single
+ :: ∀accessMode format e es b r handle
+ . (Member (ScopedFile (Mode format accessMode) es b handle) r, Member e es)
+ => Path b File -> InterpretersFor '[e, Input (Path b File)] r
+scopedFile_single path = scopedFile_bundle path . rewrite injBundle
+
+scopedFile_bundle
+ :: ∀accessMode format es b r handle
+ . Member (ScopedFile (Mode format accessMode) es b handle) r
+ => Path b File -> InterpretersFor '[Bundle es, Input (Path b File)] r
+scopedFile_bundle path = transform ScopedFile . scopedP path . raise2Under
+
+
+{- | A tag type that represents file open mode in POSIX.
+-}
+data Mode (fmt :: Format) (acc :: AccessMode)
+
+data Format =
+ TextFormat
+ | BytesFormat
+
+data AccessMode =
+ ReadAccess
+ -- ^read only access mode ('System.IO.ReadMode')
+
+ | WriteAccess
+ -- ^write only access mode ('System.IO.WriteMode')
+
+ | AppendAccess
+ -- ^append access mode ('System.IO.AppendMode')
+
+ | RwAccess
+ -- ^read write access mode ('System.IO.ReadWriteMode')
+
+-- | A type signature of interpreters for scoped file access.
+type Access format accessMode es r b =
+ ∀a
+ . (∀handle. Sem (ScopedFile (Mode format accessMode) es b handle ': r) a)
+ -> Sem r a
+
+
+rewriteScopedFile
+ :: (Sem (ScopedP (Path b File) handle (Bundle es) ': r) a -> Sem (ScopedP (Path b' File) handle' (Bundle es') ': r) a)
+ -> Sem (ScopedFile mode es b handle ': r) a
+ -> Sem (ScopedFile mode es' b' handle' ': r) a
+rewriteScopedFile f = rewrite unScopedFile >>> f >>> rewrite ScopedFile
+
+transformerToRewriter
+ :: (Sem (e0 ': e1 ': r) a -> Sem (e1 ': r) a)
+ -> Sem (e0 ': r) a -> Sem (e1 ': r) a
+transformerToRewriter f = raiseUnder >>> f
+
+rewriterToTransformer
+ :: (∀r. Sem (e0 ': r) a -> Sem (e1 ': r) a)
+ -> (∀r. Member e1 r' => Sem (e0 ': r') a -> Sem r' a)
+rewriterToTransformer f = f >>> subsume
diff --git a/src/Polysemy/FS/Scoped/ByteString.hs b/src/Polysemy/FS/Scoped/ByteString.hs
new file mode 100644
--- /dev/null
+++ b/src/Polysemy/FS/Scoped/ByteString.hs
@@ -0,0 +1,59 @@
+{-|
+Copyright : (c) Hisaket VioletRed, 2022
+License : AGPL-3.0-or-later
+Maintainer : hisaket@outlook.jp
+Stability : experimental
+Portability : POSIX
+-}
+
+module Polysemy.FS.Scoped.ByteString where
+
+import Polysemy ( embed, Embed, Members, interpret )
+import Polysemy.Resource ( Resource )
+import Polysemy.FS.Scoped
+ ( Access
+ , AccessMode ( ReadAccess, WriteAccess )
+ , Format ( BytesFormat )
+ )
+import Polysemy.SequentialAccess.ByteString as SAB
+ ( Cursor, Resize, Append, Overwrite, ReadToEnd, ReadBytes )
+import qualified System.IO as IO
+
+import Polysemy.FS.Scoped.ByteString.Internal
+import Control.Category hiding ((.))
+import qualified Polysemy.SequentialAccess as SA
+import qualified Data.ByteString as BS
+
+
+-- | An interpreter for read open mode with binary.
+readAccessToIO
+ :: Members '[Embed IO, Resource] r
+ => Access BytesFormat ReadAccess (SAB.ReadBytes ': SAB.ReadToEnd ': SAB.Cursor) r b
+readAccessToIO =
+ scopedBinaryFileToIO IO.ReadMode
+ \h -> readToIO h >>> cursorToIO h
+
+-- | An interpreter for write open mode with binary.
+writeAccessToIO
+ :: Members '[Embed IO, Resource] r
+ => Access BytesFormat WriteAccess (SAB.Overwrite ': SAB.Resize ': SAB.Cursor) r b
+writeAccessToIO =
+ scopedBinaryFileToIO IO.WriteMode
+ \h -> overwriteToIO h >>> resizeToIO h >>> cursorToIO h
+
+-- | An interpreter for read and write open mode with binary.
+rwAccessToIO
+ :: Members '[Embed IO, Resource] r
+ => Access BytesFormat WriteAccess
+ (SAB.ReadBytes ': SAB.ReadToEnd ': SAB.Overwrite ': SAB.Resize ': SAB.Cursor) r b
+rwAccessToIO =
+ scopedBinaryFileToIO IO.ReadWriteMode
+ \h -> readToIO h >>> overwriteToIO h >>> resizeToIO h >>> cursorToIO h
+
+-- | An interpreter for append open mode with binary.
+appendAccessToIO
+ :: Members '[Embed IO, Resource] r
+ => Access BytesFormat WriteAccess '[SAB.Append, SAB.Resize] r b
+appendAccessToIO =
+ scopedBinaryFileToIO IO.AppendMode
+ \h -> resizeToIO h . interpret (\(SA.Append s) -> embed $ BS.hPut h s)
diff --git a/src/Polysemy/FS/Scoped/ByteString/Internal.hs b/src/Polysemy/FS/Scoped/ByteString/Internal.hs
new file mode 100644
--- /dev/null
+++ b/src/Polysemy/FS/Scoped/ByteString/Internal.hs
@@ -0,0 +1,51 @@
+{-|
+Copyright : (c) Hisaket VioletRed, 2022
+License : AGPL-3.0-or-later
+Maintainer : hisaket@outlook.jp
+Stability : experimental
+Portability : POSIX
+-}
+
+module Polysemy.FS.Scoped.ByteString.Internal where
+import Polysemy
+ ( Member, Sem, embed, Embed, InterpretersFor, Members, interpret )
+import qualified Polysemy.SequentialAccess.ByteString as SAB
+import qualified Polysemy.SequentialAccess as SA
+import qualified Data.ByteString as BS
+import qualified GHC.IO.Handle as IO
+import qualified System.IO as IO
+import Control.Category ( (>>>) )
+import Polysemy.FS.Scoped.Internal ( seekToEnd )
+import Polysemy.Internal.Kind ( Append )
+import Polysemy.Resource ( Resource )
+import Polysemy.Internal.Sing ( KnownList )
+import qualified Polysemy.FS.Scoped.Internal as Scoped
+
+readToIO :: Member (Embed IO) r => IO.Handle -> Sem (SAB.ReadBytes ': SAB.ReadToEnd ': r) a -> Sem r a
+readToIO h =
+ interpret (\(SA.Read n) -> embed $ BS.hGet h $ fromIntegral n)
+ >>> interpret
+ ( \(SA.Read SA.ToEnd) ->
+ embed $ (BS.hGetContents =<< IO.hDuplicate h) <* seekToEnd h
+ )
+
+cursorToIO :: Member (Embed IO) r => IO.Handle -> Sem (Append SAB.Cursor r) a -> Sem r a
+cursorToIO h =
+ interpret (\SA.GetPosition -> embed $ fromIntegral <$> IO.hTell h)
+ >>> interpret (\(SA.Seek (SA.Absolute n)) -> embed $ IO.hSeek h IO.AbsoluteSeek $ fromIntegral n)
+ >>> interpret (\(SA.Seek (SA.Relative i)) -> embed $ IO.hSeek h IO.RelativeSeek i)
+ >>> interpret (\(SA.Seek (SA.FromEnd i)) -> embed $ IO.hSeek h IO.SeekFromEnd i)
+
+overwriteToIO :: Member (Embed IO) r => IO.Handle -> Sem (SAB.Overwrite ': r) a -> Sem r a
+overwriteToIO h = interpret \(SA.Overwrite s) -> embed $ BS.hPut h s
+
+resizeToIO :: Member (Embed IO) r => IO.Handle -> Sem (SAB.Resize ': r) a -> Sem r a
+resizeToIO h = interpret \(SA.Resize n) -> embed $ IO.hSetFileSize h $ fromIntegral n
+
+scopedBinaryFileToIO
+ :: (Members '[Embed IO, Resource] r, KnownList es)
+ => IO.IOMode
+ -> (IO.Handle -> InterpretersFor es r)
+ -> (∀handle'. Sem (Scoped.ScopedFile mode es b handle' ': r) a)
+ -> Sem r a
+scopedBinaryFileToIO = Scoped.scopedFileToIO IO.openBinaryFile
diff --git a/src/Polysemy/FS/Scoped/Internal.hs b/src/Polysemy/FS/Scoped/Internal.hs
new file mode 100644
--- /dev/null
+++ b/src/Polysemy/FS/Scoped/Internal.hs
@@ -0,0 +1,152 @@
+{-
+This module contains the modified source code from polysemy-1.7.1.0 package
+under 'BSD-3-Clause'. So that part is only licensed under
+'AGPL-3.0-or-later AND BSD-3-Clause', other part is licensed under
+'AGPL-3.0-or-later'.
+-}
+
+-- -----BEGIN AGPL-3.0-or-later PART-----
+-- Copyright (C) 2022 Hisaket VioletRed
+
+{-|
+License : See the header comment of the source file of this module.
+Maintainer : hisaket@outlook.jp
+Stability : experimental
+-}
+
+module Polysemy.FS.Scoped.Internal where
+
+import Polysemy
+ ( Sem, embed, Embed, InterpretersFor, Members, rewrite )
+import Polysemy.Internal.Kind ( Append )
+import Polysemy.Bundle ( runBundle, Bundle (Bundle) )
+import Polysemy.Internal.Sing
+ ( SList (SEnd, SCons), KnownList (singList) )
+import Polysemy.Internal.Union
+ ( decomp
+ , extendMembershipLeft
+ , hoist
+ , membership
+ , ElemOf
+ , Union(Union)
+ , Weaving(Weaving)
+ )
+import Polysemy.Internal
+ ( Sem, Append, embed, hoistSem, Embed, InterpretersFor, Members )
+import Polysemy.Resource ( bracket, Resource )
+import qualified System.IO as IO
+import Polysemy.Path ( toFilePath, Path, File )
+import Polysemy.Scoped.Path ( ScopedP, runScopedP )
+import Polysemy.FS.Scoped.Internal.MembersProof
+ ( MembersProof (MembersProof), membersProof, membersProofId )
+
+newtype ScopedFile mode es b handle m a =
+ ScopedFile { unScopedFile :: ScopedP (Path b File) handle (Bundle es) m a }
+
+scopedFileToIO
+ :: (Members '[Embed IO, Resource] r, KnownList es)
+ => (FilePath -> IO.IOMode -> IO IO.Handle)
+ -> IO.IOMode
+ -> (IO.Handle -> InterpretersFor es r)
+ -> (∀handle'. Sem (ScopedFile mode es b handle' ': r) a)
+ -> Sem r a
+scopedFileToIO openFile mode =
+ runScopedFile
+ (\path -> bracket (embed $ openFile (toFilePath path) mode) (embed . IO.hClose))
+
+runScopedFile
+ :: KnownList es
+ => (∀x. Path b File -> (handle -> Sem r x) -> Sem r x)
+ -> (handle -> InterpretersFor es r)
+ -> (∀handle'. Sem (ScopedFile mode es b handle' ': r) a)
+ -> Sem r a
+runScopedFile acquire interpret m =
+ runScopedP acquire (\h -> interpret h . runBundle) $ rewrite unScopedFile m
+
+
+seekToBegin :: IO.Handle -> IO ()
+seekToBegin h = IO.hSeek h IO.AbsoluteSeek 0
+
+seekToEnd :: IO.Handle -> IO ()
+seekToEnd h = IO.hSeek h IO.SeekFromEnd 0
+
+
+
+sendBundle_
+ :: ∀es r a
+ . KnownList es
+ => Sem (Append es (Bundle es ': r)) a
+ -> Sem (Bundle es ': r) a
+sendBundle_ = sendBundleSListUsingProof es $ membersProofId es
+ where es = singList @es
+
+sendBundleSList
+ :: Members l es
+ => SList l
+ -> Sem (Append l (Bundle es ': r)) a
+ -> Sem (Bundle es ': r) a
+sendBundleSList l = sendBundleSListUsingProof l $ membersProof l
+
+sendBundleSListUsingProof
+ :: ∀l es r a
+ . SList l
+ -> MembersProof l es
+ -> Sem (Append l (Bundle es ': r)) a
+ -> Sem (Bundle es ': r) a
+sendBundleSListUsingProof = \case
+ SEnd -> const id
+ SCons l ->
+ \(MembersProof pr prs) ->
+ sendBundleSListUsingProof l prs
+ . sendBundleUsing pr
+ (extendMembershipLeft @_ @(Bundle es ': r) l membership)
+
+-- -----END AGPL-3.0-or-later PART-----
+
+-- -----BEGIN AGPL-3.0-or-later AND BSD-3-Clause PART-----
+{-
+Copyright Sandy Maguire (c) 2019
+Copyright Hisaket VioletRed (c) 2022
+
+All rights reserved.
+-}
+
+-- This function is modified version from 'Polysemy.Bundle.sendBundle' in polysemy-1.7.1.0 package.
+sendBundleUsing :: ElemOf e r' -> ElemOf (Bundle r') r -> Sem (e ': r) a -> Sem r a
+sendBundleUsing prE prBundle =
+ hoistSem $ \u -> case decomp u of
+ Right (Weaving e s wv ex ins) ->
+ Union prBundle $
+ Weaving (Bundle prE e) s (sendBundleUsing prE prBundle . wv) ex ins
+ Left g -> hoist (sendBundleUsing prE prBundle) g
+{-# INLINE sendBundleUsing #-}
+
+{-
+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 Sandy Maguire 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.
+-}
+-- -----END AGPL-3.0-or-later AND BSD-3-Clause PART-----
diff --git a/src/Polysemy/FS/Scoped/Internal/MembersProof.hs b/src/Polysemy/FS/Scoped/Internal/MembersProof.hs
new file mode 100644
--- /dev/null
+++ b/src/Polysemy/FS/Scoped/Internal/MembersProof.hs
@@ -0,0 +1,34 @@
+{-|
+Copyright : (c) Hisaket VioletRed, 2022
+License : AGPL-3.0-or-later
+Maintainer : hisaket@outlook.jp
+Stability : experimental
+-}
+
+module Polysemy.FS.Scoped.Internal.MembersProof where
+
+import Polysemy ( Members, Effect, EffectRow )
+import Polysemy.Internal.Union ( membership, ElemOf (There), )
+import Polysemy.Internal.Sing ( SList (SEnd, SCons) )
+
+data MembersProof (es :: EffectRow) (r :: EffectRow) where
+ EmptyMembersProof :: MembersProof '[] r
+ MembersProof :: ElemOf e r -> MembersProof es r -> MembersProof (e ': es) r
+
+membersProof :: Members es r => SList es -> MembersProof es r
+membersProof = \case
+ SEnd -> EmptyMembersProof
+ SCons xs -> MembersProof membership $ membersProof xs
+
+membersProofId :: SList l -> MembersProof l l
+membersProofId = \case
+ SEnd -> EmptyMembersProof
+ SCons xs -> weakenIdMP $ membersProofId xs
+
+weakenIdMP :: MembersProof l l -> MembersProof (e ': l) (e ': l)
+weakenIdMP pr = MembersProof membership $ weakenRightMP pr
+
+weakenRightMP :: MembersProof es r -> MembersProof es (e ': r)
+weakenRightMP = \case
+ EmptyMembersProof -> EmptyMembersProof
+ MembersProof pf pfs -> MembersProof (There pf) $ weakenRightMP pfs
diff --git a/src/Polysemy/FS/Scoped/Oneshot.hs b/src/Polysemy/FS/Scoped/Oneshot.hs
new file mode 100644
--- /dev/null
+++ b/src/Polysemy/FS/Scoped/Oneshot.hs
@@ -0,0 +1,158 @@
+{-|
+Copyright : (c) Hisaket VioletRed, 2022
+License : AGPL-3.0-or-later
+Maintainer : hisaket@outlook.jp
+Stability : experimental
+
+Unscoped file access and interop with polysemy-fs package.
+-}
+
+{-# OPTIONS_GHC -Wno-unrecognised-pragmas #-}
+{-# HLINT ignore "Use camelCase" #-}
+{-# LANGUAGE PartialTypeSignatures #-}
+
+module Polysemy.FS.Scoped.Oneshot where
+
+import Polysemy ( Member, Sem, Members, interpret )
+import Polysemy.FS.Scoped
+ ( ScopedFile
+ , AccessMode (ReadAccess, AppendAccess, WriteAccess)
+ , Format (TextFormat, BytesFormat)
+ , Mode
+ , scopedFile_single
+ )
+import qualified Polysemy.SequentialAccess.Text as SAT
+import qualified Polysemy.SequentialAccess.ByteString as SAB
+import qualified Polysemy.SequentialAccess as SA
+import Polysemy.Path
+ ( toFilePath
+ , parseSomeFile
+ , Path
+ , Abs
+ , File
+ , PathException
+ , Rel
+ , SomeBase
+ )
+import Polysemy.Error ( Error )
+import Control.Category ( (>>>) )
+import qualified Data.ByteString as BS
+import Path ( SomeBase (..) )
+import Prelude hiding ( readFile, appendFile )
+import qualified Polysemy.FS.Scoped.Text as ST
+import qualified Polysemy.FS.Scoped.ByteString as SB
+import Polysemy.FS
+ ( FSRead (ReadFileBS, ReadFileUtf8)
+ , FSWrite (WriteFileBS, WriteFileUtf8)
+ )
+
+readFile
+ :: (Member (ScopedFile (Mode fmt ReadAccess) es b handle) r, Member (SA.Read SA.ToEnd i) es)
+ => Path b File -> Sem r i
+readFile path = scopedFile_single path $ SA.read SA.ToEnd
+
+overwriteFile
+ :: (Member (ScopedFile (Mode fmt WriteAccess) es b handle) r, Member (SA.Overwrite o) es)
+ => Path b File -> o -> Sem r ()
+overwriteFile path o = scopedFile_single path $ SA.overwrite o
+
+extendFile
+ :: (Member (ScopedFile (Mode fmt WriteAccess) es b handle) r, Member (SA.Extend o) es)
+ => Path b File -> o -> Sem r ()
+extendFile path o = scopedFile_single path $ SA.extend o
+
+appendFile
+ :: (Member (ScopedFile (Mode fmt AppendAccess) es b handle) r, Member (SA.Append o) es)
+ => Path b File -> o -> Sem r ()
+appendFile path o = scopedFile_single path $ SA.append o
+
+readFile_single
+ :: Member (ScopedFile (Mode fmt ReadAccess) '[SA.Read SA.ToEnd i] b handle) r
+ => Path b File -> Sem r i
+readFile_single = readFile
+
+overwriteFile_single
+ :: Member (ScopedFile (Mode fmt WriteAccess) '[SA.Overwrite o] b handle) r
+ => Path b File -> o -> Sem r ()
+overwriteFile_single = overwriteFile
+
+extendFile_single
+ :: Member (ScopedFile (Mode fmt WriteAccess) '[SA.Extend o] b handle) r
+ => Path b File -> o -> Sem r ()
+extendFile_single = extendFile
+
+appendFile_single
+ :: Member (ScopedFile (Mode fmt AppendAccess) '[SA.Append o] b handle) r
+ => Path b File -> o -> Sem r ()
+appendFile_single = appendFile
+
+
+
+{- | Example:
+
+>>> import Polysemy.Resource ( resourceToIO )
+>>> import qualified Polysemy.FS.Scoped.Text as ST
+>>> import qualified Polysemy.FS.Scoped.ByteString as SB
+>>> import Polysemy.Scoped.Path ( weakenScopedP )
+>>> import Polysemy.FS.Scoped ( rewriteScopedFile, transformerToRewriter )
+>>> import Polysemy ( runFinal, embedToFinal, subsume_ )
+>>> import Polysemy.Error ( errorToIOFinal )
+>>> :{
+ fsReadToIO :: Sem '[FSRead] a -> IO (Either PathException a)
+ fsReadToIO m =
+ runFinal $ embedToFinal $ resourceToIO $ errorToIOFinal
+ $ ST.readAccessToIO $ rewriteScopedFile (transformerToRewriter $ weakenScopedP @'[SAT.ReadToEnd] @_ @(Path Abs _))
+ $ ST.readAccessToIO $ rewriteScopedFile (transformerToRewriter $ weakenScopedP @'[SAT.ReadToEnd] @_ @(Path Rel _))
+ $ SB.readAccessToIO $ rewriteScopedFile (transformerToRewriter $ weakenScopedP @'[SAB.ReadToEnd] @_ @(Path Abs _))
+ $ SB.readAccessToIO $ rewriteScopedFile (transformerToRewriter $ weakenScopedP @'[SAB.ReadToEnd] @_ @(Path Rel _))
+ $ fsReadToScopedRead
+ $ subsume_ m
+:}
+
+-}
+
+fsReadToScopedRead
+ :: ∀handle0 handle1 handle2 handle3 r a
+ . Members
+ '[ ScopedFile (Mode BytesFormat ReadAccess) '[SAB.ReadToEnd] Abs handle0
+ , ScopedFile (Mode BytesFormat ReadAccess) '[SAB.ReadToEnd] Rel handle1
+ , ScopedFile (Mode TextFormat ReadAccess) '[SAT.ReadToEnd] Abs handle2
+ , ScopedFile (Mode TextFormat ReadAccess) '[SAT.ReadToEnd] Rel handle3
+ , Error PathException
+ ] r
+ => Sem (FSRead ': r) a
+ -> Sem r a
+fsReadToScopedRead = interpret \case
+ ReadFileBS path ->
+ toSomeBase path >>= \case
+ Abs path -> readFile @BytesFormat path
+ Rel path -> readFile @BytesFormat path
+ ReadFileUtf8 path ->
+ toSomeBase path >>= \case
+ Abs path -> readFile @TextFormat path
+ Rel path -> readFile @TextFormat path
+
+fsWriteToScopedWrite
+ :: ∀handle0 handle1 handle2 handle3 r a
+ . Members
+ '[ ScopedFile (Mode BytesFormat WriteAccess) '[SAB.Overwrite] Abs handle0
+ , ScopedFile (Mode BytesFormat WriteAccess) '[SAB.Overwrite] Rel handle1
+ , ScopedFile (Mode TextFormat WriteAccess) '[SAT.Extend] Abs handle2
+ , ScopedFile (Mode TextFormat WriteAccess) '[SAT.Extend] Rel handle3
+ , Error PathException
+ ] r
+ => Sem (FSWrite ': r) a
+ -> Sem r a
+fsWriteToScopedWrite = interpret \case
+ WriteFileBS path content ->
+ toSomeBase path >>= \case
+ Abs path -> overwriteFile @BytesFormat path content
+ Rel path -> overwriteFile @BytesFormat path content
+ WriteFileUtf8 path content ->
+ toSomeBase path >>= \case
+ Abs path -> extendFile @TextFormat path content
+ Rel path -> extendFile @TextFormat path content
+
+toSomeBase :: Members '[Error PathException] r => Path b File -> Sem r (SomeBase File)
+toSomeBase = toFilePath >>> parseSomeFile
+-- Perhaps, an error can't occur definitely so the error effect can be removed...
diff --git a/src/Polysemy/FS/Scoped/Text.hs b/src/Polysemy/FS/Scoped/Text.hs
new file mode 100644
--- /dev/null
+++ b/src/Polysemy/FS/Scoped/Text.hs
@@ -0,0 +1,87 @@
+{-|
+Copyright : (c) Hisaket VioletRed, 2022
+License : AGPL-3.0-or-later
+Maintainer : hisaket@outlook.jp
+Stability : experimental
+Portability : POSIX
+
+Example\:
+
+>>> import qualified Polysemy.SequentialAccess as SA
+>>> import qualified Polysemy.SequentialAccess.Text as SAT
+>>> import Polysemy ( runFinal, embedToFinal, embed )
+>>> import Polysemy.Resource ( resourceToIOFinal )
+>>> import Polysemy.Path
+>>> import Polysemy.FS.Scoped ( scopedFile, AccessMode (RwAccess) )
+>>> import Control.Monad.Extra ( whenM )
+>>> import System.Directory ( doesFileExist, removeFile )
+>>> import Control.Exception ( throwIO )
+>>> :{
+runFinal $ embedToFinal $ resourceToIOFinal $ rwAccessToIO do
+ let path = [absfile|/tmp/polysemy-scoped-fs-test|]
+ embed $ whenM (doesFileExist $ toFilePath path) $
+ throwIO $ userError "Abort to prevent overwriting."
+ scopedFile @RwAccess path do
+ SA.extend "This text will be deleted."
+ SA.resize SA.NullSize
+ SA.extend "foo"
+ SA.extend "bar"
+ SA.seek SA.TOF
+ embed . print =<< SA.read SA.ToEnd
+ embed $ removeFile $ toFilePath path
+:}
+"foobar"
+
+-}
+
+module Polysemy.FS.Scoped.Text where
+
+import Polysemy.FS.Scoped.Text.Internal
+ ( readToIO, extendToIO, clearToIO, cursorToIO, scopedTextFileToIO )
+
+import Polysemy ( embed, Embed, Members, interpret )
+import Polysemy.FS.Scoped
+ ( Access
+ , AccessMode (ReadAccess, AppendAccess, RwAccess, WriteAccess)
+ , Format (TextFormat)
+ )
+import qualified Polysemy.SequentialAccess.Text as SAT
+import qualified System.IO as IO
+import qualified Data.Text.IO as TIO
+import qualified Polysemy.SequentialAccess as SA
+import Control.Category ( (>>>) )
+import Polysemy.Resource ( Resource )
+
+
+-- | An interpreter for read open mode with text.
+readAccessToIO
+ :: Members '[Embed IO, Resource] r
+ => Access TextFormat ReadAccess (SAT.ReadLine ': SAT.ReadToEnd ': SAT.Cursor) r b
+readAccessToIO =
+ scopedTextFileToIO IO.ReadMode
+ \h -> readToIO h >>> cursorToIO h
+
+-- | An interpreter for write open mode with text.
+writeAccessToIO
+ :: Members '[Embed IO, Resource] r
+ => Access TextFormat WriteAccess (SAT.Extend ': SAT.Clear ': SAT.Cursor) r b
+writeAccessToIO =
+ scopedTextFileToIO IO.WriteMode
+ \h -> extendToIO h >>> clearToIO h >>> cursorToIO h
+
+-- | An interpreter for read and write open mode with text.
+rwAccessToIO
+ :: Members '[Embed IO, Resource] r
+ => Access TextFormat RwAccess
+ (SAT.ReadLine ': SAT.ReadToEnd ': SAT.Extend ': SAT.Clear ': SAT.Cursor) r b
+rwAccessToIO =
+ scopedTextFileToIO IO.ReadWriteMode
+ \h -> readToIO h >>> extendToIO h >>> clearToIO h >>> cursorToIO h
+
+-- | An interpreter for append open mode with text.
+appendAccessToIO
+ :: Members '[Embed IO, Resource] r
+ => Access TextFormat AppendAccess '[SAT.Append, SAT.Clear] r b
+appendAccessToIO =
+ scopedTextFileToIO IO.AppendMode
+ \h -> clearToIO h . interpret \(SA.Append t) -> embed $ TIO.hPutStr h t
diff --git a/src/Polysemy/FS/Scoped/Text/Internal.hs b/src/Polysemy/FS/Scoped/Text/Internal.hs
new file mode 100644
--- /dev/null
+++ b/src/Polysemy/FS/Scoped/Text/Internal.hs
@@ -0,0 +1,70 @@
+{-|
+Copyright : (c) Hisaket VioletRed, 2022
+License : AGPL-3.0-or-later
+Maintainer : hisaket@outlook.jp
+Stability : experimental
+Portability : POSIX
+-}
+
+module Polysemy.FS.Scoped.Text.Internal where
+
+import qualified System.IO as IO
+import Polysemy
+ ( Member, Sem, embed, Embed, InterpretersFor, Members, interpret )
+import qualified Polysemy.SequentialAccess.Text as SAT
+import qualified Polysemy.SequentialAccess as SA
+import Polysemy.Internal.Kind ( Append )
+import Polysemy.Resource ( Resource )
+import Control.Category ( (>>>) )
+import Data.Functor ( (<&>) )
+import Polysemy.FS.Scoped.Internal as Scoped
+ ( ScopedFile, scopedFileToIO, seekToBegin, seekToEnd )
+import qualified Polysemy.FS.Scoped as Scoped
+import Polysemy.Internal.Sing ( KnownList )
+import qualified Data.Text.IO as TIO
+import qualified GHC.IO.Handle as IO
+
+
+readToIO :: Member (Embed IO) r => IO.Handle -> Sem (SAT.ReadLine ': SAT.ReadToEnd ': r) a -> Sem r a
+readToIO h =
+ interpret (\(SA.Read SAT.Line) -> embed $ TIO.hGetLine h)
+ >>> interpret
+ ( \(SA.Read SA.ToEnd) ->
+ embed $ (TIO.hGetContents =<< IO.hDuplicate h) <* seekToEnd h
+ )
+
+extendToIO :: Member (Embed IO) r => IO.Handle -> Sem (SAT.Extend ': r) a -> Sem r a
+extendToIO h = interpret \(SA.Extend t) -> embed $ restoreCursor h $ seekToEnd h *> TIO.hPutStr h t
+
+
+restoreCursor :: IO.Handle -> IO a -> IO a
+restoreCursor h m = do
+ before <- IO.hTell h
+ m <* IO.hSeek h IO.AbsoluteSeek before
+
+clearToIO :: Member (Embed IO) r => IO.Handle -> Sem (SAT.Clear ': r) a -> Sem r a
+clearToIO h = interpret \(SA.Resize SA.NullSize) -> embed $ IO.hSetFileSize h 0
+
+cursorToIO :: Member (Embed IO) r => IO.Handle -> Sem (Append SAT.Cursor r) a -> Sem r a
+cursorToIO h =
+ interpret
+ ( \SA.GetPosition -> embed $
+ IO.hTell h >>= \case
+ 0 -> pure $ SA.End SA.TOF
+ _ -> IO.hIsEOF h <&> \case
+ False -> SA.Intermediate
+ True -> SA.End SA.EOF
+ )
+ >>> interpret
+ (\(SA.Seek end) -> embed $ case end of
+ SA.TOF -> seekToBegin h
+ SA.EOF -> seekToEnd h
+ )
+
+scopedTextFileToIO
+ :: (Members '[Embed IO, Resource] r, KnownList es)
+ => IO.IOMode
+ -> (IO.Handle -> InterpretersFor es r)
+ -> (∀handle'. Sem (Scoped.ScopedFile mode es b handle' ': r) a)
+ -> Sem r a
+scopedTextFileToIO = Scoped.scopedFileToIO IO.openFile
diff --git a/src/Polysemy/Scoped/Path.hs b/src/Polysemy/Scoped/Path.hs
new file mode 100644
--- /dev/null
+++ b/src/Polysemy/Scoped/Path.hs
@@ -0,0 +1,168 @@
+{-
+This module contains the modified source code from polysemy-conc-0.7.0.0 package
+under 'BSD-2-Clause-Patent'. So that part is only licensed under
+'AGPL-3.0-or-later AND BSD-2-Clause-Patent', other part is licensed under
+'AGPL-3.0-or-later'.
+-}
+
+-- -----BEGIN AGPL-3.0-or-later PART-----
+-- Copyright (C) 2022 Hisaket VioletRed
+
+{-|
+License : See the header comment of the source file of this module.
+Maintainer : hisaket@outlook.jp
+Stability : experimental
+Portability : POSIX
+-}
+
+{-# OPTIONS_GHC -Wno-unrecognised-pragmas #-}
+{-# HLINT ignore "Use camelCase" #-}
+
+module Polysemy.Scoped.Path
+ ( module Polysemy.Scoped.Path
+ , Polysemy.Scoped.Path.Internal.ScopedP
+ )
+ where
+
+import Polysemy
+ ( Member
+ , Sem
+ , raise
+ , InterpreterFor
+ , InterpretersFor
+ , Members
+ , transform
+ )
+import Polysemy.Internal ( liftSem, send )
+import Polysemy.Internal.Union ( injWeaving, Weaving(Weaving) )
+import Control.Category ( (>>>) )
+import Polysemy.Input ( Input, runInputConst )
+import Polysemy.Bundle ( injBundle, Bundle )
+import Polysemy.Scoped.Path.Internal
+ ( ScopedP (Run, InScope), bundle, unbundle, weakenBundle, interpretH' )
+import Polysemy.Internal.Sing ( KnownList )
+
+
+-- | Variant of 'scopedP' in which cannot access to outer scope.
+innerScopedP :: Member (ScopedP path resource (Bundle es)) r => path -> Sem es a -> Sem r a
+innerScopedP path = scopedP path . bundle
+
+injScopedP
+ :: ∀effect es path resource r a
+ . (Member (ScopedP path resource (Bundle es)) r, Member effect es)
+ => Sem (ScopedP path resource effect ': r) a -> Sem r a
+injScopedP = transformScopedP injBundle
+
+unbundleScopedP
+ :: Member (ScopedP path resource effect) r
+ => Sem (ScopedP path resource (Bundle '[effect]) ': r) a -> Sem r a
+unbundleScopedP = transformScopedP unbundle
+
+weakenScopedP
+ :: ∀es0 es1 path resource r a
+ . (Member (ScopedP path resource (Bundle es1)) r, Members es0 es1, KnownList es0)
+ => Sem (ScopedP path resource (Bundle es0) ': r) a -> Sem r a
+weakenScopedP = transformScopedP weakenBundle
+
+transformScopedP
+ :: (Member (ScopedP path resource e1) r)
+ => (∀rInitial x. e0 (Sem rInitial) x -> e1 (Sem rInitial) x)
+ -> Sem (ScopedP path resource e0 ': r) a
+ -> Sem r a
+transformScopedP f = transform \case
+ Run res e -> Run res $ f e
+ InScope path f -> InScope path f
+
+
+type Scoped = ScopedP ()
+
+scoped :: Member (Scoped resource effect) r => InterpreterFor effect r
+scoped = scopedP_simple ()
+
+
+scopedP
+ :: ∀path resource effect r
+ . Member (ScopedP path resource effect) r
+ => path -> InterpretersFor '[effect, Input path] r
+scopedP path =
+ scopedP_simple path
+ >>> runInputConst path
+
+-- -----END AGPL-3.0-or-later PART-----
+
+-- -----BEGIN AGPL-3.0-or-later AND BSD-2-Clause-Patent PART-----
+{-
+Copyright (c) 2020 Torsten Schmits
+Copyright (c) 2022 Hisaket VioletRed
+-}
+
+-- The below functions are modified (or unmodified) version from modules
+-- 'Polysemy.Conc.Effect.Scoped' and 'Polysemy.Conc.Interpreter.Scoped' in
+-- polysemy-conc-0.7.0.0 package.
+
+scopedP_simple
+ :: ∀e path resource effect r a
+ . Member (ScopedP path resource effect) r
+ => path -> InterpreterFor effect r
+scopedP_simple path main =
+ send $ InScope path \resource ->
+ transform @effect (Run resource) main
+
+scopedP_local
+ :: ∀e path resource effect r a
+ . Member (ScopedP path resource effect) r
+ => (resource -> resource) -> path -> InterpreterFor effect r
+scopedP_local f path main =
+ send $ InScope path \resource ->
+ transform @effect (Run $ f resource) main
+
+runScopedP
+ :: ∀path resource effect r
+ . (∀x. path -> (resource -> Sem r x) -> Sem r x)
+ -> (resource -> InterpreterFor effect r)
+ -> InterpreterFor (ScopedP path resource effect) r
+runScopedP withResource scopedInterpreter = run
+ where
+ run :: InterpreterFor (ScopedP path resource effect) r
+ run =
+ interpretH' \(Weaving effect s wv ex ins) -> case effect of
+ Run resource act ->
+ scopedInterpreter resource (liftSem $ injWeaving $ Weaving act s (raise . run . wv) ex ins)
+ InScope path main ->
+ ex <$> withResource path \resource -> run (wv (main resource <$ s))
+
+{-
+Redistribution and use in source and binary forms, with or without modification, are permitted provided that the
+following conditions are met:
+
+ 1. Redistributions of source code must retain the above copyright notice, this list of conditions and the following
+ disclaimer.
+ 2. 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.
+
+Subject to the terms and conditions of this license, each copyright holder and contributor hereby grants to those
+receiving rights under this license a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable (except
+for failure to satisfy the conditions of this license) patent license to make, have made, use, offer to sell, sell,
+import, and otherwise transfer this software, where such license applies only to those patent claims, already acquired
+or hereafter acquired, licensable by such copyright holder or contributor that are necessarily infringed by:
+
+ (a) their Contribution(s) (the licensed copyrights of copyright holders and non-copyrightable additions of
+ contributors, in source or binary form) alone; or
+ (b) combination of their Contribution(s) with the work of authorship to which such Contribution(s) was added by such
+ copyright holder or contributor, if, at the time the Contribution is added, such addition causes such combination to
+ be necessarily infringed. The patent license shall not apply to any other combinations which include the Contribution.
+
+Except as expressly stated above, no rights or licenses from any copyright holder or contributor is granted under this
+license, whether expressly, by implication, estoppel or otherwise.
+
+DISCLAIMER
+
+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 HOLDERS 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.
+-}
+-- -----END AGPL-3.0-or-later AND BSD-2-Clause-Patent PART-----
diff --git a/src/Polysemy/Scoped/Path/Internal.hs b/src/Polysemy/Scoped/Path/Internal.hs
new file mode 100644
--- /dev/null
+++ b/src/Polysemy/Scoped/Path/Internal.hs
@@ -0,0 +1,128 @@
+{-
+This module contains the modified source code from polysemy-conc-0.7.0.0 package
+under 'BSD-2-Clause-Patent'. So that part is only licensed under
+'AGPL-3.0-or-later AND BSD-2-Clause-Patent', other part is licensed under
+'AGPL-3.0-or-later'.
+-}
+
+-- -----BEGIN AGPL-3.0-or-later PART-----
+-- Copyright (C) 2022 Hisaket VioletRed
+
+{-|
+License : See the header comment of the source file of this module.
+Maintainer : hisaket@outlook.jp
+Stability : experimental
+Portability : POSIX
+-}
+
+{-# LANGUAGE EmptyCase #-}
+
+{-# OPTIONS_GHC -Wno-unrecognised-pragmas #-}
+{-# HLINT ignore "Use camelCase" #-}
+
+module Polysemy.Scoped.Path.Internal where
+
+import Polysemy ( Sem, InterpreterFor, Members )
+import Polysemy.Internal.Union
+ ( decomp, hoist, membership
+ , Union (Union), Weaving (Weaving), ElemOf (Here, There)
+ )
+import Polysemy.Internal
+ ( Sem (Sem, runSem), hoistSem, InterpreterFor, Members )
+import Control.Category ((>>>))
+import Polysemy.FS.Scoped.Internal.MembersProof ( MembersProof )
+import Polysemy.Internal.Sing ( SList (SEnd, SCons), KnownList (singList) )
+import Polysemy.Bundle ( Bundle (Bundle) )
+
+-- | Bundle all effects of 'Sem' into a single 'Bundle'.
+bundle :: Sem es a -> Sem (Bundle es ': r) a
+bundle =
+ hoistSem \(Union w (Weaving e s wv ex ins)) ->
+ Union Here $ Weaving (Bundle w e) s (bundle . wv) ex ins
+
+
+subsumeBundle_id :: Sem (Bundle r ': r) a -> Sem r a
+subsumeBundle_id = subsumeBundleUsing id
+
+subsumeBundleUsing :: (∀e. ElemOf e es -> ElemOf e r) -> Sem (Bundle es ': r) a -> Sem r a
+subsumeBundleUsing i = hoistSem $ \u -> hoist (subsumeBundleUsing i) $ case decomp u of
+ Right (Weaving (Bundle pr e) s wv ex ins) ->
+ Union (i pr) (Weaving e s wv ex ins)
+ Left g -> g
+
+
+unbundle :: Bundle '[e] m a -> e m a
+unbundle = \case
+ Bundle Here e -> e
+ Bundle (There es) e -> case es of
+
+weakenBundle :: (Members es r, KnownList es) => Bundle es m a -> Bundle r m a
+weakenBundle (Bundle pr e) = Bundle (weakenMembership pr) e
+
+
+weakenMembership :: (Members es r, KnownList es) => ElemOf e es -> ElemOf e r
+weakenMembership = weakenMembership' singList
+
+weakenMembership' :: Members es r => SList es -> ElemOf e es -> ElemOf e r
+weakenMembership' l pr = case l of
+ SEnd -> case pr of
+ SCons xs -> case pr of
+ Here -> membership
+ There pr' -> weakenMembership' xs pr'
+
+-- -----END AGPL-3.0-or-later PART-----
+
+-- -----BEGIN AGPL-3.0-or-later AND BSD-2-Clause-Patent PART-----
+{-
+Copyright (c) 2020 Torsten Schmits
+Copyright (c) 2022 Hisaket VioletRed
+-}
+
+data ScopedP path resource effect m a where
+ Run :: ∀path resource effect m a. resource -> effect m a -> ScopedP path resource effect m a
+ InScope :: ∀path resource effect m a. path -> (resource -> m a) -> ScopedP path resource effect m a
+
+interpretH'
+ :: (∀x. Weaving e (Sem (e : r)) x -> Sem r x)
+ -> InterpreterFor e r
+interpretH' h (Sem m) =
+ Sem \k -> m $ decomp >>> \case
+ Right wav -> runSem (h wav) k
+ Left g -> k $ hoist (interpretH' h) g
+
+
+{-
+Redistribution and use in source and binary forms, with or without modification, are permitted provided that the
+following conditions are met:
+
+ 1. Redistributions of source code must retain the above copyright notice, this list of conditions and the following
+ disclaimer.
+ 2. 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.
+
+Subject to the terms and conditions of this license, each copyright holder and contributor hereby grants to those
+receiving rights under this license a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable (except
+for failure to satisfy the conditions of this license) patent license to make, have made, use, offer to sell, sell,
+import, and otherwise transfer this software, where such license applies only to those patent claims, already acquired
+or hereafter acquired, licensable by such copyright holder or contributor that are necessarily infringed by:
+
+ (a) their Contribution(s) (the licensed copyrights of copyright holders and non-copyrightable additions of
+ contributors, in source or binary form) alone; or
+ (b) combination of their Contribution(s) with the work of authorship to which such Contribution(s) was added by such
+ copyright holder or contributor, if, at the time the Contribution is added, such addition causes such combination to
+ be necessarily infringed. The patent license shall not apply to any other combinations which include the Contribution.
+
+Except as expressly stated above, no rights or licenses from any copyright holder or contributor is granted under this
+license, whether expressly, by implication, estoppel or otherwise.
+
+DISCLAIMER
+
+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 HOLDERS 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.
+-}
+-- -----END AGPL-3.0-or-later AND BSD-2-Clause-Patent PART-----
diff --git a/src/Polysemy/Scoped/Path/Isolation.hs b/src/Polysemy/Scoped/Path/Isolation.hs
new file mode 100644
--- /dev/null
+++ b/src/Polysemy/Scoped/Path/Isolation.hs
@@ -0,0 +1,63 @@
+{-|
+Copyright : (c) Hisaket VioletRed, 2022
+License : AGPL-3.0-or-later
+Maintainer : hisaket@outlook.jp
+Stability : experimental
+
+This module provides methods that allow for isolating effects inside or outside the scope locally.
+
+It will be useful when using the effects for virtualization or containerization such as libvirt or Docker safely.
+-}
+
+{-# OPTIONS_GHC -Wno-unrecognised-pragmas #-}
+{-# HLINT ignore "Use camelCase" #-}
+
+module Polysemy.Scoped.Path.Isolation where
+import Polysemy ( Member, Sem, InterpretersFor, Members, rewrite )
+import Polysemy.Scoped.Path ( ScopedP, scopedP )
+import Polysemy.Input ( Input )
+import Polysemy.Bundle ( subsumeBundle, Bundle )
+import Control.Category ( (>>>) )
+import Polysemy.Scoped.Path.Internal
+ ( bundle, subsumeBundleUsing, unbundle )
+import Polysemy.Tagged ( tag, untag, Tagged )
+import Polysemy.Membership ( ElemOf )
+
+-- | Variant of 'scopedP' that can isolate effects inside or outside the scope locally.
+isolatingScopedP
+ :: Member (ScopedP path resource effect) r
+ => path -> InterpretersFor '[Tagged 'Inner effect, Input path, Tagged 'Outer (Bundle r)] r
+isolatingScopedP = isolatingScopedPSubUsing id
+
+-- | Variant of 'scopedP' that can isolate effects inside or outside the scope locally.
+-- A version that can isolate only a subset of effects in regards to outside the scope.
+isolatingScopedPSub
+ :: ∀es path resource effect r
+ . (Member (ScopedP path resource effect) r, Members es r)
+ => path -> InterpretersFor '[Tagged 'Inner effect, Input path, Tagged 'Outer (Bundle es)] r
+isolatingScopedPSub path = untag >>> scopedP path >>> untag >>> subsumeBundle
+
+-- | Variant of 'scopedP' that can isolate effects inside or outside the scope locally.
+isolatingScopedPSubUsing
+ :: ∀es path resource effect r
+ . Member (ScopedP path resource effect) r
+ => (∀e. ElemOf e es -> ElemOf e r)
+ -> path -> InterpretersFor '[Tagged 'Inner effect, Input path, Tagged 'Outer (Bundle es)] r
+isolatingScopedPSubUsing f path = untag >>> scopedP path >>> untag >>> subsumeBundleUsing f
+
+data ScopeSide =
+ Inner -- ^ A tag type that represents effects inside the scope.
+ | Outer -- ^ A tag type that represents effects outside the scope.
+
+-- | Isolate only effects inside the scope.
+inScope :: Member (Tagged Inner (Bundle es)) r => Sem es a -> Sem r a
+inScope = bundle >>> tag
+
+-- | Isolate only effects inside the scope.
+-- No bundle version.
+inScope_single :: Member (Tagged Inner eff) r => Sem '[eff] a -> Sem r a
+inScope_single = bundle >>> rewrite unbundle >>> tag
+
+-- | Isolate only effects outside the scope.
+outScope :: Member (Tagged Outer (Bundle es)) r => Sem es a -> Sem r a
+outScope = bundle >>> tag
diff --git a/src/Polysemy/ScopedReader.hs b/src/Polysemy/ScopedReader.hs
new file mode 100644
--- /dev/null
+++ b/src/Polysemy/ScopedReader.hs
@@ -0,0 +1,91 @@
+{-|
+Copyright : (c) Hisaket VioletRed, 2022
+License : AGPL-3.0-or-later
+Maintainer : hisaket@outlook.jp
+Stability : experimental
+
+This module provides a scoped-reader manner.
+
+In contrast to a normal 'Reader' effect, this manner makes connection of parameter type and effect explicit.
+
+Example\:
+
+>>> import Polysemy ( interpret, runM, embed )
+>>> import Polysemy.Output ( Output (Output), output, runOutputSem )
+
+>>> :{
+runDebug :: Member (Output String) r => String -> InterpreterFor (ScopedReader String (Output String)) r
+runDebug = runScopedReader \i -> interpret \(Output o) -> output $ "[" <> i <> "] " <> o
+:}
+
+>>> :{
+runM $ runOutputSem (embed . putStrLn) $ runDebug "root" do
+ scopedReader $ output "test message 0"
+ scopedLocal (<> ".scope-A") do
+ scopedReader $ output "test message 1"
+ scopedReader $ output "test message 2"
+ scopedLocal (<> ".scope-B") do
+ scopedReader $ output "test message 3"
+:}
+[root] test message 0
+[root.scope-A] test message 1
+[root.scope-A] test message 2
+[root.scope-A.scope-B] test message 3
+
+-}
+
+{-# LANGUAGE PartialTypeSignatures #-}
+{-# OPTIONS_GHC -Wno-partial-type-signatures #-}
+
+module Polysemy.ScopedReader where
+
+import Polysemy
+ ( Member, Sem, raise, raiseUnder, InterpreterFor, transform )
+import Polysemy.Scoped.Path ( ScopedP, scopedP_local, runScopedP )
+import Polysemy.Scoped.Path.Internal ( interpretH' )
+import Control.Category ((>>>))
+import Polysemy.Internal ( liftSem )
+import Polysemy.Internal.Union
+ ( ElemOf (Here), Union (Union), Weaving (Weaving) )
+
+
+scopedLocal
+ :: ∀i p resource effect r
+ . Member (ScopedReader i effect) r
+ => (i -> i) -> InterpreterFor (ScopedFix i effect) r
+scopedLocal f = scopedFix . scopedP_local f () . raiseUnder
+
+scopedReader :: Member (ScopedReader i effect) r => Sem (effect ': r) a -> Sem r a
+scopedReader = scopedEffect
+
+type ScopedReader i effect = ScopedFix i effect
+
+runScopedReader :: (i -> InterpreterFor effect r) -> i -> Sem (ScopedReader i effect ': r) a -> Sem r a
+runScopedReader int localEnv =
+ interpretH' \(Weaving e s wv ex ins) ->
+ let send' :: _ -> Sem (_ ': _) _
+ send' e' =
+ liftSem $ Union Here
+ $ Weaving e' s (raise . runScopedReader int localEnv . wv) ex ins
+ in case e of
+ ScopedEffect e' -> int localEnv $ send' e'
+ ScopedFix e' ->
+ runScopedP (\() inner -> inner localEnv) (runScopedReader int) $ send' e'
+
+
+data ScopedFixP p resource effect m a where
+ ScopedEffect :: effect m a -> ScopedFixP p resource effect m a
+ ScopedFix
+ :: ScopedP p resource (ScopedFixP p resource effect) m a
+ -> ScopedFixP p resource effect m a
+
+type ScopedFix = ScopedFixP ()
+
+scopedEffect :: Member (ScopedFixP p resource effect) r => Sem (effect ': r) a -> Sem r a
+scopedEffect = transform ScopedEffect
+
+scopedFix
+ :: Member (ScopedFixP p resource effect) r
+ => Sem (ScopedP p resource (ScopedFixP p resource effect) ': r) a
+ -> Sem r a
+scopedFix = transform ScopedFix
diff --git a/src/Polysemy/SequentialAccess.hs b/src/Polysemy/SequentialAccess.hs
new file mode 100644
--- /dev/null
+++ b/src/Polysemy/SequentialAccess.hs
@@ -0,0 +1,122 @@
+{-|
+Copyright : (c) Hisaket VioletRed, 2022
+License : AGPL-3.0-or-later
+Maintainer : hisaket@outlook.jp
+Stability : experimental
+Portability : POSIX
+-}
+
+module Polysemy.SequentialAccess where
+
+import Polysemy ( Member, Sem, interpret, makeSem )
+import Prelude hiding ( Read, read )
+import Polysemy.Input ( Input (Input) )
+import Polysemy.Output ( Output (Output) )
+
+
+data GetPosition pos m a where
+ GetPosition :: GetPosition pos m pos
+{- ^An effect that gets the current cursor position in the file.
+-}
+makeSem ''GetPosition
+
+{- |A type that represents both ends or intermediate positions in the file.
+-}
+data TriPosition = End Ends | Intermediate
+ deriving (Eq, Ord, Show)
+
+{- |A type that represents both ends of the file.
+-}
+data Ends =
+ TOF -- ^Top of file
+ | EOF -- ^End of file
+ deriving (Eq, Ord, Show)
+
+
+data Seek pos m a where
+ Seek :: pos -> Seek pos m ()
+{- ^An effect that moves the cursor.
+-}
+makeSem ''Seek
+
+{- |A wrapper type that represents an absolute position in the file.
+-}
+newtype Absolute a = Absolute a deriving (Eq, Ord, Show)
+
+{- |A wrapper type that represents relative position from the current cursor position.
+-}
+newtype Relative a = Relative a deriving (Eq, Ord, Show)
+
+{- |A wrapper type that represents relative position from the end of the file.
+-}
+newtype FromEnd a = FromEnd a deriving (Eq, Ord, Show)
+
+
+data Read sz i m a where
+ Read :: sz -> Read sz i m i
+{- ^An effect that gets file contents by the size 'sz' from the current
+ position.
+-}
+makeSem ''Read
+
+{- |An effect that gets file contents from current position to the end of the
+ file.
+-}
+type ReadToEnd = Read ToEnd
+
+{- |A singleton that represents the size from the current position to the end of
+ the file.
+-}
+data ToEnd = ToEnd deriving (Eq, Ord, Show)
+
+-- |A singleton that represents the size 0.
+data NullSize = NullSize deriving (Eq, Ord, Show)
+
+{- |Transforms an 'Input' effect into an 'Read' effect with the fixed size.
+-}
+inputToRead :: Member (Read sz i) r => sz -> Sem (Input i ': r) a -> Sem r a
+inputToRead sz = interpret \Input -> read sz
+
+
+data Overwrite o m a where
+ Overwrite :: o -> Overwrite o m ()
+{- ^An effect that overwrites file contents by the data 'o' from current
+ position.
+-}
+makeSem ''Overwrite
+
+{- |Transforms an 'Output' effect into an `Overwrite` effect.
+-}
+outputToOverwrite :: Member (Overwrite o) r => Sem (Output o ': r) a -> Sem r a
+outputToOverwrite = interpret \(Output o) -> overwrite o
+
+
+data Extend o m a where
+ Extend :: o -> Extend o m ()
+-- ^An effect that extends a file by the data 'o' from the end of a file.
+-- The cursor is not moved.
+makeSem ''Extend
+
+data Append o m a where
+ Append :: o -> Append o m ()
+-- ^An effect that extends a file by the data 'o' from the end of a file.
+-- The cursor is moved to the end of the file after extending.
+makeSem ''Append
+
+{- |Transforms an 'Output' effect into an `Extend` effect.
+-}
+outputToExtend :: Member (Extend o) r => Sem (Output o ': r) a -> Sem r a
+outputToExtend = interpret \(Output o) -> extend o
+
+-- |Transforms an 'Output' effect into an `Append` effect.
+outputToAppend :: Member (Append o) r => Sem (Output o ': r) a -> Sem r a
+outputToAppend = interpret \(Output o) -> append o
+
+
+data Resize sz m a where
+ Resize :: sz -> Resize sz m ()
+{- ^An effect that resizes a file by the size 'sz'.
+
+ Note: The initial data in space made by a growing is interpreter-dependent.
+-}
+makeSem ''Resize
diff --git a/src/Polysemy/SequentialAccess/ByteString.hs b/src/Polysemy/SequentialAccess/ByteString.hs
new file mode 100644
--- /dev/null
+++ b/src/Polysemy/SequentialAccess/ByteString.hs
@@ -0,0 +1,29 @@
+{-|
+Description : Sequential access for binary data
+Copyright : (c) Hisaket VioletRed, 2022
+License : AGPL-3.0-or-later
+Maintainer : hisaket@outlook.jp
+Stability : experimental
+Portability : POSIX
+
+This module is for sequential access to binary data.
+
+In sequential access for binary data, it is allowed to read data by arbitrary
+size, and overwrite to, and seek to an arbitrary position.
+-}
+
+module Polysemy.SequentialAccess.ByteString where
+
+import qualified Polysemy.SequentialAccess as SA
+import Data.ByteString ( ByteString )
+import Numeric.Natural ( Natural )
+
+type GetPosition = SA.GetPosition Natural
+type ReadBytes = SA.Read Natural ByteString
+type ReadToEnd = SA.Read SA.ToEnd ByteString
+type Overwrite = SA.Overwrite ByteString
+type Append = SA.Append ByteString
+type Resize = SA.Resize Natural
+
+type Seek = '[SA.Seek (SA.Absolute Natural), SA.Seek (SA.Relative Integer), SA.Seek (SA.FromEnd Integer)]
+type Cursor = GetPosition ': Seek
diff --git a/src/Polysemy/SequentialAccess/Text.hs b/src/Polysemy/SequentialAccess/Text.hs
new file mode 100644
--- /dev/null
+++ b/src/Polysemy/SequentialAccess/Text.hs
@@ -0,0 +1,37 @@
+{-|
+Description : Sequential access for variable-width encoded text data
+Copyright : (c) Hisaket VioletRed, 2022
+License : AGPL-3.0-or-later
+Maintainer : hisaket@outlook.jp
+Stability : experimental
+Portability : POSIX
+
+This module is for sequential access to variable-width encoded text data.
+
+In sequential access for variable-width encoded (e.g. UTF-8) text data, It is
+allowed to read data per line instead of by arbitrary size.
+And, seek operation is only allowed to both ends of a file.
+
+This restriction of safety assumes no writing from others while opening a file.
+The behavior is undefined if the assumption is not satisfied. (An encoding corruption occurs typically.)
+-}
+
+module Polysemy.SequentialAccess.Text where
+
+import qualified Polysemy.SequentialAccess as SA
+import Data.Text ( Text )
+
+type GetPosition = SA.GetPosition SA.TriPosition
+type Seek = SA.Seek SA.Ends
+type ReadLine = SA.Read Line Text
+type ReadToEnd = SA.Read SA.ToEnd Text
+type Extend = SA.Extend Text
+type Append = SA.Append Text
+type Clear = SA.Resize SA.NullSize
+
+{- |A singleton that represents the size from the current position to the next
+ line break.
+-}
+data Line = Line deriving (Eq, Ord, Show)
+
+type Cursor = '[GetPosition, Seek]
diff --git a/test/Spec.hs b/test/Spec.hs
new file mode 100644
--- /dev/null
+++ b/test/Spec.hs
@@ -0,0 +1,2 @@
+main :: IO ()
+main = putStrLn "Test suite not yet implemented"
diff --git a/test/doctests.hs b/test/doctests.hs
new file mode 100644
--- /dev/null
+++ b/test/doctests.hs
@@ -0,0 +1,31 @@
+module Main where
+
+import Test.DocTest
+
+main :: IO ()
+main = doctest $
+ map ("-X" <>) exts
+ <> ["-fplugin=Polysemy.Plugin"]
+ <> ["-isrc", "src/Polysemy/FS/Scoped/Text.hs"]
+ <> ["-isrc", "src/Polysemy/ScopedReader.hs"]
+ <> ["-isrc", "src/Polysemy/FS/Scoped/Oneshot.hs"]
+
+-- TODO: fetch automatically from package.yaml
+exts :: [String]
+exts =
+ [ "DataKinds"
+ , "FlexibleContexts"
+ , "GADTs"
+ , "LambdaCase"
+ , "PolyKinds"
+ , "RankNTypes"
+ , "ScopedTypeVariables"
+ , "TypeApplications"
+ , "TypeOperators"
+ , "TypeFamilies"
+ , "UnicodeSyntax"
+ , "BlockArguments"
+ , "TemplateHaskell"
+ , "QuasiQuotes"
+ , "OverloadedStrings"
+ ]