Add merge builder for raise #3061

kyay10 · 2023-05-28T17:30:47Z

I re-implemented some of Effect/s methods using the merge builder to check its functionality.

Note for the future: when/if union types are in the language, merge should likely be deprecated in favour of a union builder that has separate types for the returned and raised types (so that they're inferred separately) and returning a union of both.

Co-authored-by: Simon Vergauwen <nomisRev@users.noreply.github.com>

serras · 2023-05-31T14:35:48Z

arrow-libs/core/arrow-core/src/commonMain/kotlin/arrow/core/raise/Builders.kt

@@ -25,7 +25,7 @@ public inline fun <Error, A> either(@BuilderInference block: Raise<Error>.() ->
  fold({ block.invoke(this) }, { Either.Left(it) }, { Either.Right(it) })

 public inline fun <A> nullable(block: NullableRaise.() -> A): A? =
-  fold({ block(NullableRaise(this)) }, { null }, ::identity)
+  merge { block(NullableRaise(this)) }


I don't fully understand why this works...

TL;DR: nullable is just secretly a restricted merge because it's taking Raise<Nothing?>.() -> A and returning A?, which is the supertype of Nothing? and A.
Note also that instead of { null } in the original code, you could've had ::identity, and hence merge(blah) == fold(blah, ::identity, ::identity)

In other words, nullable is a general example of returning the common supertype of the raised and the returned (except of course that we have NullableRaise to provide nice binds for related types like Option due to the lack of context receiver support right now)

Side note: In the future when we have union types, this pattern would work with a lot more types, but right now, this just utilises the fact that ? is the only natively supported union type in Kotlin. Btw, I think the design for union types prevents them from being automatically inferred (i.e. the compiler won't infer a type parameter T to a union type ever, but it respects explicit mentions of union types) and so a union builder that infers the types separately and returns a union of them would be the way to go when that happens

I am amazed by the fact that you could find this (cool) approximation 🤯

With a powerful type system, the possibilities are infinite! 🚀

franciscodr

Thanks, @kyay10! Amazing contribution 🚀

# Conflicts: # arrow-libs/core/arrow-core/src/commonMain/kotlin/arrow/core/raise/Raise.kt # arrow-libs/core/arrow-core/src/jvmTest/kotlin/examples/example-raise-dsl-11.kt

[![Mend Renovate](https://app.renovatebot.com/images/banner.svg)](https://renovatebot.com) This PR contains the following updates: | Package | Change | Age | Adoption | Passing | Confidence | |---|---|---|---|---|---| | [io.arrow-kt:arrow-optics-ksp-plugin](https://togithub.com/arrow-kt/arrow) | `1.1.5` -> `1.2.0` | [![age](https://badges.renovateapi.com/packages/maven/io.arrow-kt:arrow-optics-ksp-plugin/1.2.0/age-slim)](https://docs.renovatebot.com/merge-confidence/) | [![adoption](https://badges.renovateapi.com/packages/maven/io.arrow-kt:arrow-optics-ksp-plugin/1.2.0/adoption-slim)](https://docs.renovatebot.com/merge-confidence/) | [![passing](https://badges.renovateapi.com/packages/maven/io.arrow-kt:arrow-optics-ksp-plugin/1.2.0/compatibility-slim/1.1.5)](https://docs.renovatebot.com/merge-confidence/) | [![confidence](https://badges.renovateapi.com/packages/maven/io.arrow-kt:arrow-optics-ksp-plugin/1.2.0/confidence-slim/1.1.5)](https://docs.renovatebot.com/merge-confidence/) | | [io.arrow-kt:arrow-optics](https://togithub.com/arrow-kt/arrow) | `1.1.5` -> `1.2.0` | [![age](https://badges.renovateapi.com/packages/maven/io.arrow-kt:arrow-optics/1.2.0/age-slim)](https://docs.renovatebot.com/merge-confidence/) | [![adoption](https://badges.renovateapi.com/packages/maven/io.arrow-kt:arrow-optics/1.2.0/adoption-slim)](https://docs.renovatebot.com/merge-confidence/) | [![passing](https://badges.renovateapi.com/packages/maven/io.arrow-kt:arrow-optics/1.2.0/compatibility-slim/1.1.5)](https://docs.renovatebot.com/merge-confidence/) | [![confidence](https://badges.renovateapi.com/packages/maven/io.arrow-kt:arrow-optics/1.2.0/confidence-slim/1.1.5)](https://docs.renovatebot.com/merge-confidence/) | | [io.arrow-kt:arrow-core](https://togithub.com/arrow-kt/arrow) | `1.1.5` -> `1.2.0` | [![age](https://badges.renovateapi.com/packages/maven/io.arrow-kt:arrow-core/1.2.0/age-slim)](https://docs.renovatebot.com/merge-confidence/) | [![adoption](https://badges.renovateapi.com/packages/maven/io.arrow-kt:arrow-core/1.2.0/adoption-slim)](https://docs.renovatebot.com/merge-confidence/) | [![passing](https://badges.renovateapi.com/packages/maven/io.arrow-kt:arrow-core/1.2.0/compatibility-slim/1.1.5)](https://docs.renovatebot.com/merge-confidence/) | [![confidence](https://badges.renovateapi.com/packages/maven/io.arrow-kt:arrow-core/1.2.0/confidence-slim/1.1.5)](https://docs.renovatebot.com/merge-confidence/) | --- ### Release Notes <details> <summary>arrow-kt/arrow (io.arrow-kt:arrow-optics-ksp-plugin)</summary> ### [`v1.2.0`](https://togithub.com/arrow-kt/arrow/releases/tag/1.2.0) [Compare Source](https://togithub.com/arrow-kt/arrow/compare/1.1.5...1.2.0) #### What's Changed - Add CNAME file to Dokka output by [@franciscodr](https://togithub.com/franciscodr) in [arrow-kt/arrow#3029 - Remove legacy site code by [@nomisRev](https://togithub.com/nomisRev) in [arrow-kt/arrow#3030 - Update README by [@serras](https://togithub.com/serras) in [arrow-kt/arrow#3033 - Cancel previous PR action on new commit by [@nomisRev](https://togithub.com/nomisRev) in [arrow-kt/arrow#3032 - Remove legacy script files by [@franciscodr](https://togithub.com/franciscodr) in [arrow-kt/arrow#3034 - Ensure optics type with "data" modifier is a class by [@DeoTimeTheGithubUser](https://togithub.com/DeoTimeTheGithubUser) in [arrow-kt/arrow#3036 - Update all dependencies (major) by [@renovate](https://togithub.com/renovate) in [arrow-kt/arrow#3042 - Remove test dependency from Arrow Fx by [@nomisRev](https://togithub.com/nomisRev) in [arrow-kt/arrow#3046 - Bump Kotlin, KSP and coroutines version by [@nomisRev](https://togithub.com/nomisRev) in [arrow-kt/arrow#3047 - fix mapIndexed when collecting multiple times by [@hoc081098](https://togithub.com/hoc081098) in [arrow-kt/arrow#3056 - Update versions by [@nomisRev](https://togithub.com/nomisRev) in [arrow-kt/arrow#3058 - optics ksp plugin: fixed handling of variance ([#3057](https://togithub.com/arrow-kt/arrow/issues/3057)) by [@vladd-g](https://togithub.com/vladd-g) in [arrow-kt/arrow#3060 - Fixes recover inconsistency with raise DSL on types other than Either by [@yoxjames](https://togithub.com/yoxjames) in [arrow-kt/arrow#3052 - Change NonEmptySet type parameter name from T to A by [@franciscodr](https://togithub.com/franciscodr) in [arrow-kt/arrow#3062 - Add withError and (Eager)Effect.mapError by [@kyay10](https://togithub.com/kyay10) in [arrow-kt/arrow#3059 - Update versions of several libraries by [@serras](https://togithub.com/serras) in [arrow-kt/arrow#3017 - Add merge builder for raise by [@kyay10](https://togithub.com/kyay10) in [arrow-kt/arrow#3061 - Update all dependencies by [@renovate](https://togithub.com/renovate) in [arrow-kt/arrow#3065 - Update dependency gradle to v8.2 by [@renovate](https://togithub.com/renovate) in [arrow-kt/arrow#3070 - Fix warnings of single-subclass sealed classes by [@jooohn](https://togithub.com/jooohn) in [arrow-kt/arrow#3067 - KDoc for `Raise#raise`, `Raise#ensure` and `Raise#ensureNotNull` by [@ILIYANGERMANOV](https://togithub.com/ILIYANGERMANOV) in [arrow-kt/arrow#3038 - Fix text repetition in EffectScope's deprecation message by [@serras](https://togithub.com/serras) in [arrow-kt/arrow#3072 - Introduce `NonEmptyCollection` by [@serras](https://togithub.com/serras) in [arrow-kt/arrow#3068 - Set up Spotless by [@serras](https://togithub.com/serras) in [arrow-kt/arrow#3075 - Update all dependencies by [@renovate](https://togithub.com/renovate) in [arrow-kt/arrow#3079 - Add option to disable `inline` when using `@optics` by [@serras](https://togithub.com/serras) in [arrow-kt/arrow#3078 - Update JS versions in `yarn.lock` by [@serras](https://togithub.com/serras) in [arrow-kt/arrow#3084 - Enable Automatic Modules for JVM by [@serras](https://togithub.com/serras) in [arrow-kt/arrow#3071 - Serialization module by [@serras](https://togithub.com/serras) in [arrow-kt/arrow#3077 - Add missing docs for `Raise` operations by [@serras](https://togithub.com/serras) in [arrow-kt/arrow#3082 - Add mapOrAccumulate extension in RaiseAccumulate by [@nomisRev](https://togithub.com/nomisRev) in [arrow-kt/arrow#3086 - Additional tests for `copy` in Optics by [@serras](https://togithub.com/serras) in [arrow-kt/arrow#3089 - Apply Gradle Versioning in top project by [@serras](https://togithub.com/serras) in [arrow-kt/arrow#3092 - Add missing Versioning plug-in to `arrow-core-retrofit` by [@serras](https://togithub.com/serras) in [arrow-kt/arrow#3093 - Update `arrow-gradle-config` to 0.12-rc.4 by [@serras](https://togithub.com/serras) in [arrow-kt/arrow#3094 - MemoizedDeepRecursiveFunction by [@serras](https://togithub.com/serras) in [arrow-kt/arrow#3091 - Add reset and barrierAction to CyclicBarrier. by [@HSAR](https://togithub.com/HSAR) in [arrow-kt/arrow#3055 - \[HOTFIX] Fix main publish by [@nomisRev](https://togithub.com/nomisRev) in [arrow-kt/arrow#3095 #### New Contributors - [@DeoTimeTheGithubUser](https://togithub.com/DeoTimeTheGithubUser) made their first contribution in [arrow-kt/arrow#3036 - [@vladd-g](https://togithub.com/vladd-g) made their first contribution in [arrow-kt/arrow#3060 - [@yoxjames](https://togithub.com/yoxjames) made their first contribution in [arrow-kt/arrow#3052 - [@kyay10](https://togithub.com/kyay10) made their first contribution in [arrow-kt/arrow#3059 - [@jooohn](https://togithub.com/jooohn) made their first contribution in [arrow-kt/arrow#3067 - [@ILIYANGERMANOV](https://togithub.com/ILIYANGERMANOV) made their first contribution in [arrow-kt/arrow#3038 - [@HSAR](https://togithub.com/HSAR) made their first contribution in [arrow-kt/arrow#3055 **Full Changelog**: arrow-kt/arrow@1.2.0-RC...1.2.0 </details> --- ### Configuration 📅 **Schedule**: Branch creation - At any time (no schedule defined), Automerge - At any time (no schedule defined). 🚦 **Automerge**: Enabled. ♻ **Rebasing**: Whenever PR becomes conflicted, or you tick the rebase/retry checkbox. 🔕 **Ignore**: Close this PR and you won't be reminded about these updates again. --- - [ ] If you want to rebase/retry this PR, check this box --- This PR has been generated by [Mend Renovate](https://www.mend.io/free-developer-tools/renovate/). View repository job log [here](https://developer.mend.io/github/sindrenm/android-project-template).

Co-authored-by: Simon Vergauwen <nomisRev@users.noreply.github.com> Co-authored-by: Francisco Diaz <francisco.d@47deg.com>

Add withError and (Eager)Effect.mapError

4a77e70

kyay10 force-pushed the merge-builder branch from a279678 to 31e4491 Compare May 28, 2023 17:31

kyay10 mentioned this pull request May 28, 2023

Add withError and (Eager)Effect.mapError #3059

Merged

kyay10 and others added 2 commits May 28, 2023 18:55

Remove Raise receiver from mapError.

85e8456

Apply suggestions from code review

6155991

Co-authored-by: Simon Vergauwen <nomisRev@users.noreply.github.com>

serras reviewed May 31, 2023

View reviewed changes

Add merge builder for raise.

f53dd98

kyay10 force-pushed the merge-builder branch from 31e4491 to f53dd98 Compare May 31, 2023 20:34

Merge branch 'main' into merge-builder

7898647

franciscodr approved these changes Jun 1, 2023

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Merge branch 'main' into main

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serras approved these changes Jun 2, 2023

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franciscodr added 2 commits June 7, 2023 06:47

Merge remote-tracking branch 'origin/main' into merge-builder

c216213

# Conflicts: # arrow-libs/core/arrow-core/src/commonMain/kotlin/arrow/core/raise/Raise.kt # arrow-libs/core/arrow-core/src/jvmTest/kotlin/examples/example-raise-dsl-11.kt

Merge remote-tracking branch 'main' into merge-builder

3fa33d2

nomisRev approved these changes Jun 19, 2023

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nomisRev merged commit 3d7cb6e into arrow-kt:main Jun 19, 2023
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renovate bot mentioned this pull request Aug 6, 2023

fix(deps): update all non-major dependencies santa-close/santa-close-server#162

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kyay10 added a commit to kyay10/arrow that referenced this pull request Aug 18, 2023

Add merge builder for raise (arrow-kt#3061)

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Co-authored-by: Simon Vergauwen <nomisRev@users.noreply.github.com> Co-authored-by: Francisco Diaz <francisco.d@47deg.com>

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Add merge builder for raise #3061

Add merge builder for raise #3061

kyay10 commented May 28, 2023

serras May 31, 2023

kyay10 May 31, 2023 •

edited

serras May 31, 2023

kyay10 May 31, 2023

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Add merge builder for raise #3061

Add merge builder for raise #3061

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kyay10 commented May 28, 2023

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kyay10 May 31, 2023 • edited

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kyay10 May 31, 2023 •

edited