polysemy/ChangeLog.md

# Changelog for polysemy

## Unreleased

## 1.9.1.0 (2023-04-09)

### Other Changes

* Support GHC 9.6

### Breaking Changes

### Other Changes

## 1.9.0.0 (2022-12-28)

### Breaking Changes
- Slightly modified the signatures of the various `Scoped` interpreters.

### Other Changes
- Added `runScopedNew`, a simple but powerful `Scoped` interpreter.
  `runScopedNew` can be considered a sneak-peek of the future of `Scoped`,
  which will eventually receive a major API rework to make it both simpler and
  more expressive.
- Fixed a bug in various `Scoped` interpreters where a `scoped` usage of an
  effect always relied on the nearest enclosing use of `scoped` from the same
  `Scoped` effect, rather than the `scoped` which handles the effect.
- Added `Polysemy.Opaque`, a module for the `Opaque` effect newtype, meant as
  a tool to wrap polymorphic effect variables so they don't jam up resolution of
  `Member` constraints.
- Expose the type alias `Scoped_` for a scoped effect without callsite parameters.

## 1.8.0.0 (2022-12-22)

### Breaking Changes

- Removed `Polysemy.View`
- Removed `Polysemy.Law`
- Removed `(@)` and `(@@)` from `Polysemy`
- Removed `withLowerToIO` from `Polysemy`. Use `withWeavingToFinal` instead.
- Removed `asyncToIO` and `lowerAsync` from `Polysemy.Async`. Use
    `asyncToIOFinal` instead.
- Removed `lowerEmbedded` from `Polysemy.IO`. Use `embedToMonadIO` instead.
- Removed `lowerError` from `Polysemy.Error`. Use `errorToIOFinal` instead.
- Removed `resourceToIO` and `lowerResource` from `Polysemy.Resource`. Use
    `resourceToIOFinal` instead.
- Removed `runFixpoint` and `runFixpointM` from `Polysemy.Fixpoint`. Use
    `fixpointToFinal` instead.
- Changed semantics of `errorToIOFinal` so that it no longer catches errors
  from other handlers of the same type.
- The semantics of `runScoped` has been changed so that the provided interpreter
  is now used only once per use of `scoped`, instead of each individual action.

### Other Changes

- Exposed `send` from `Polysemy`.
- Dramatically improved build performance of projects when compiling with `-O2`.
- Removed the debug `dump-core` flag.
- Introduced the new meta-effect `Scoped`, which allows running an interpreter locally whose implementation is deferred
  to a later stage.
- Fixed a bug in various `Scoped` interpreters where any explicit recursive
  interpretation of higher-order computations that the handler may perform are
  ignored by the interpreter, and the original handler was reused instead.

## 1.7.1.0 (2021-11-23)

### Other Changes

* Support GHC 9.2.1

## 1.7.0.0 (2021-11-16)

### Breaking Changes

* Added interpreters for `AtomicState` that run in terms of `State`.
* Removed `MemberWithError`
* Removed `DefiningModule`

### Other Changes

* The internal `ElemOf` proof is now implemented as an unsafe integer,
    significantly cutting down on generated core.
* Polysemy no longer emits custom type errors for ambiguous effect actions.
    These have long been rendered moot by `polysemy-plugin`, and the cases that
    they still exist are usually overeager (and wrong.)
* As a result, the core produced by `polysemy` is significantly smaller.
    Programs should see a reduction of ~20% in terms and types, and ~60% in
    coercions.

## 1.6.0.0 (2021-07-12)

### Breaking Changes

* Deprecate `traceToIO` and replace it with `traceToStdout` and `traceToStderr`
* Support GHC 9.0.1

### Other Changes

* Added the combinator `insertAt`, which allows adding effects at a specified index into the effect stack
* Added `Semigroup` and `Monoid` for `Sem`

## 1.5.0.0 (2021-03-30)

### Breaking Changes
* Dropped support for GHC 8.4

### Other Changes
- Added `InterpretersFor` as a shorthand for interpreters consuming multiple effects
- Added `runTSimple` and `bindTSimple`, which are simplified variants of `runT` and `bindT`

## 1.4.0.0 (2020-10-31)

### Breaking Changes
- Added `Polysemy.Async.cancel` to allow cancelling `Async` action (possible name collision)
  ([#321](https://github.com/polysemy-research/polysemy/pull/321), thanks to @aidangilmore)

### Other Changes
- Added `Polysemy.Input.inputs` to mirror `Polysemy.Reader.asks`
  ([#327](https://github.com/polysemy-research/polysemy/issues/327), thanks to @expipiplus1)
- Added `Polysemy.Resource.bracket_`
  ([#335](https://github.com/polysemy-research/polysemy/pull/335), thanks to @expipiplus1)
- Support GHC 8.10.x
  ([#337](https://github.com/polysemy-research/polysemy/pull/337), [#382](https://github.com/polysemy-research/polysemy/pull/382))
- Restrict the existentially quantified monad in a `Weaving` to `Sem r`
  ([#333](https://github.com/polysemy-research/polysemy/pull/333), thanks to @A1kmm)
- Added `raise2Under` and `raise3Under`
  ([#369](https://github.com/polysemy-research/polysemy/pull/369))
- Added `Raise` and `Subsume`
  ([#370](https://github.com/polysemy-research/polysemy/pull/370))
- Fixed memory leaks in `Applicative (Sem r)` methods
  ([#372](https://github.com/polysemy-research/polysemy/pull/372), thanks to @goertzenator)
-  Smaller suggestions and fixes (thanks to @jeremyschlatter, @galagora and @felixonmars)

## 1.3.0.0 (2020-02-14)

### Breaking Changes
- The semantics for `runNonDet` when `<|>` is used inside a higher-order action
    of another effect has been reverted to that of 1.1.0.0 and earlier.
    (See [issue #246](https://github.com/polysemy-research/polysemy/issues/246))
- Type parameters for `outputToTrace` have been rearranged (thanks to
    @juanpaucar)

### Other Changes
- Added `Bundle` effect, for bundling multiple effects into a single one.
- Added `Tagged` effect, for annotating and disambiguating identical effects.
- Added `View` effect, an `Input`-like effect for caching an expensive
    computation.
- Added `fromException`/`Via` and `fromExceptionSem`/`Via`
- Added `note`
- Added `catchJust`, `try` and `tryJust` (thanks to @bolt12)
- Using `listen` with `runWriterTVar` or `writerToIO` will no longer delay writing
    until the `listen` completes.
- Added `runStateSTRef` and `stateToST` (thanks to @incertia)
- Added `execState` and `execLazyState` (thanks to @tjweir)
- Added `Polysemy.Law`, which offers machinery for creating laws for effects.
- Added `Polysemy.Membership` for retrieving and making use of effect membership
    proofs.

## 1.2.3.0 (2019-10-29)

- Polysemy now works on GHC 8.8.1 (thanks to @googleson78 and @sevanspowell)
- Exported `MemberWithError` from `Polysemy`
- Added `rewrite` and `transform` interpretation combinators

## 1.2.2.0 (2019-10-22)

- Fixed a bug in `resourceToIO` and `resourceToIOFinal` that prevented the
    finalizers from being called in `BracketOnError` when the computation failed
    due to a `Sem` failure
- Added `atomicGets` (thanks to @googleson78)
- Added `sequenceConcurrently` to `Polysemy.Async` (thanks to @spacekitteh)

## 1.2.1.0 (2019-09-15)

- Added `InterpreterFor` (thanks to @bolt12)
- Bumped bounds for first-class-families

## 1.2.0.0 (2019-09-04)

### Breaking Changes

- All `lower-` interpreters have been deprecated, in favor of corresponding
    `-Final` interpreters.
- `runFixpoint` and `runFixpointM` have been deprecated in favor of
    `fixpointToFinal`.
- The semantics for `runNonDet` when `<|>` is used inside a higher-order action
    of another effect has been changed.
- Type variables for certain internal functions, `failToEmbed`, and
    `atomicState'` have been rearranged.

### Other changes

- Added `Final` effect, an effect for embedding higher-order actions in the
    final monad of the effect stack. Any interpreter should use this instead of
    requiring to be provided an explicit lowering function to the final monad.
- Added `Strategy` environment for use together with `Final`
- Added `asyncToIOFinal`, a better alternative of `lowerAsync`
- Added `errorToIOFinal`, a better alternative of `lowerError`
- Added `fixpointToFinal`, a better alternative of `runFixpoint` and `runFixpointM`
- Added `resourceToIOFinal`, a better alternative of `lowerResource`
- Added `outputToIOMonoid` and `outputToIOMonoidAssocR`
- Added `stateToIO`
- Added `atomicStateToIO`
- Added `runWriterTVar`, `writerToIOFinal`, and `writerToIOAssocRFinal`
- Added `writerToEndoWriter`
- Added `subsume` operation
- Exposed `raiseUnder`/`2`/`3` in `Polysemy`


## 1.1.0.0 (2019-08-15)

### Breaking Changes

- `MonadFail` is now implemented in terms of `Fail`, instead of `NonDet` (thanks to @KingoftheHomeless)
- `LastMember` has been removed. `withLowerToIO` and all interpreters that make use of it
    now only requires `Member (Embed IO) r` (thanks to @KingoftheHomeless)
- `State` and `Writer` now have better strictness semantics

### Other Changes

- Added `AtomicState` effect (thanks to @KingoftheHomeless)
- Added `Fail` effect (thanks to @KingoftheHomeless)
- Added `runOutputSem` (thanks to @cnr)
- Added `modify'`, a strict variant of `modify` (thanks to @KingoftheHomeless)
- Added right-associative variants of `runOutputMonoid` and `runWriter` (thanks to @KingoftheHomeless)
- Added `runOutputMonoidIORef` and `runOutputMonoidTVar` (thanks to @KingoftheHomeless)
- Improved `Fixpoint` so it won't always diverge (thanks to @KingoftheHomeless)
- `makeSem` will now complain if `DataKinds` isn't enabled (thanks to @pepegar)


## 1.0.0.0 (2019-07-24)

### Breaking Changes

- Renamed `Lift`  to `Embed` (thanks to @googleson78)
- Renamed `runAsyncInIO` to `lowerAsync`
- Renamed `runAsync` to `asyncToIO`
- Renamed `runBatchOutput` to `runOutputBatched`
- Renamed `runConstInput` to `runInputConst`
- Renamed `runEmbed` to `runEmbedded` (thanks to @googleson78)
- Renamed `runEmbedded` to `lowerEmbedded`
- Renamed `runErrorAsAnother` to `mapError`
- Renamed `runErrorInIO` to `lowerError`
- Renamed `runFoldMapOutput` to `runOutputMonoid`
- Renamed `runIO` to `embedToMonadIO`
- Renamed `runIgnoringOutput` to `ignoreOutput`
- Renamed `runIgnoringTrace` to `ignoreTrace`
- Renamed `runInputAsReader` to `inputToReader`
- Renamed `runListInput` to `runInputList`
- Renamed `runMonadicInput` to `runInputSem`
- Renamed `runOutputAsList` to `runOutputList`
- Renamed `runOutputAsTrace` to `outputToTrace`
- Renamed `runOutputAsWriter` to `outputToWriter`
- Renamed `runResourceBase` to `resourceToIO`
- Renamed `runResourceInIO` to `lowerResource`
- Renamed `runStateInIORef` to `runStateIORef`
- Renamed `runTraceAsList` to `runTraceList`
- Renamed `runTraceAsOutput` to `traceToOutput`
- Renamed `runTraceIO` to `traceToIO`
- Renamed `sendM` to `embed` (thanks to @googleson78)
- The `NonDet` effect is now higher-order (thanks to @KingoftheHomeless)

### Other Changes

- Added `evalState` and `evalLazyState`
- Added `runNonDetMaybe` (thanks to @KingoftheHomeless)
- Added `nonDetToError` (thanks to @KingoftheHomeless)
- Haddock documentation for smart constructors generated via `makeSem` will no
    longer have weird variable names (thanks to @TheMatten)


## 0.7.0.0 (2019-07-08)

### Breaking Changes

- Added a `Pass` constructor to `Writer` (thanks to @KingoftheHomeless)
- Fixed a bug in `runWriter` where the MTL semantics wouldn't be respected (thanks to @KingoftheHomeless)
- Removed the `Censor` constructor of `Writer` (thanks to @KingoftheHomeless)
- Renamed `Yo` to `Weaving`
- Changed the visible type applications for `asks`, `gets`, `runEmbedded`, `fromEitherM` and `runErrorAsAnother`

### Other Changes

- Fixed haddock generation

## 0.6.0.0 (2019-07-04)

### Breaking Changes

- Changed the type of `runBatchOutput` to be more useful (thanks to @Infinisil)

### Other Changes

- **THE ERROR MESSAGES ARE SO MUCH BETTER** :party: :party: :party:
- Added `runEmbedded` to `Polysemy.IO`
- Added `runOutputAsList` to `Polysemy.Output` (thanks to @googleson78)
- Asymptotically improved the performance of `runTraceAsList` (thanks to
    @googleson78)

## 0.5.1.0 (2019-06-28)

- New combinators for `Polysemy.Error`: `fromEither` and `fromEitherM`

## 0.5.0.1 (2019-06-27)

- Fixed a bug where `intercept` and `interceptH` wouldn't correctly handle
    higher-order effects

## 0.5.0.0 (2019-06-26)

### Breaking Changes

- Removed the internal `Effect` machinery

### New Effects and Interpretations

- New effect; `Async`, for describing asynchronous computations
- New interpretation for `Resource`: `runResourceBase`, which can lower
    `Resource` effects without giving a lowering natural transformation
- New interpretation for `Trace`: `runTraceAsList`
- New combinator: `withLowerToIO`, which is capable of transforming
    `IO`-invariant functions as effects.

### Other Changes

- Lots of hard work on the package and CI infrastructure to make it green on
    GHC 8.4.4 (thanks to @jkachmar)
- Changed the order of the types for `runMonadicInput` to be more helpful
    (thanks to @tempname11)
- Improved the error machinery to be more selective about when it runs
- Factored out the TH into a common library for third-party consumers

## 0.4.0.0 (2019-06-12)

### Breaking Changes

- Renamed `runResource` to `runResourceInIO`

### Other Changes

- Added `runResource`, which runs a `Resource` purely
- Added `onException`, `finally` and `bracketOnError` to `Resource`
- Added a new function, `runResource` which performs bracketing for pure code

## 0.3.0.1 (2019-06-09)

- Fixed a type error in the benchmark caused by deprecation of `Semantic`

## 0.3.0.0 (2019-06-01)

### Breaking Changes

- Removed all deprecated names
- Moved `Random` effect to `polysemy-zoo`

### Other Changes

- `makeSem` can now be used to create term-level operators (thanks to
    @TheMatten)

## 0.2.2.0 (2019-05-30)

- Added `getInspectorT` to the `Tactical` functions, which allows polysemy code
    to be run in external callbacks
- A complete rewrite of `Polysemy.Internal.TH.Effect` (thanks to @TheMatten)
- Fixed a bug in the TH generation of effects where the splices could contain
    usages of effects that were ambiguous

## 0.2.1.0 (2019-05-27)

- Fixed a bug in the `Alternative` instance for `Sem`, where it would choose the
    *last* success instead of the first
- Added `MonadPlus` and `MonadFail` instances for `Sem`

## 0.2.0.0 (2019-05-23)

### Breaking Changes

- Lower precedence of `.@` and `.@@` to 8, from 9

### Other Changes

- Fixed a serious bug in `interpretH` and friends, where higher-order effects
    would always be run with the current interpreter.
- Users need no longer require `inlineRecursiveCalls` --- the
    `polysemy-plugin-0.2.0.0` will do  it automatically when compiling with `-O`
- Deprecated `inlineRecursiveCalls`; slated for removal in the next version

## 0.1.2.1 (2019-05-18)

- Give explicit package bounds for dependencies
- Haddock improvements
- Remove `Typeable` machinery from `Polysemy.Internal.Union` (thanks to
    @googleson78)

## 0.1.2.0 (2019-04-26)

- `runInputAsReader`, `runTraceAsOutput` and `runOutputAsWriter` have more
    generalized types
- Added `runStateInIO`
- Added `runOutputAsTrace`
- Added `Members` (thanks to @TheMatten)


## 0.1.1.0 (2019-04-14)

- Added `runIO` interpretation (thanks to @adamConnerSax)
- Minor documentation fixes


## 0.1.0.0 (2019-04-11)

- Initial release