From 6bc29305cdbb02e469f851ea1e72a42ebfc65db7 Mon Sep 17 00:00:00 2001
From: Alejandro Serrano <trupill@gmail.com>
Date: Sun, 7 Aug 2022 16:48:01 +0200
Subject: [PATCH 1/3] Enable builder inference for optics `copy`

---
 arrow-libs/optics/arrow-optics/api/arrow-optics.api  |  3 +++
 arrow-libs/optics/arrow-optics/build.gradle.kts      |  4 ++++
 .../src/commonMain/kotlin/arrow/optics/Copy.kt       | 12 ++++++++++--
 3 files changed, 17 insertions(+), 2 deletions(-)

diff --git a/arrow-libs/optics/arrow-optics/api/arrow-optics.api b/arrow-libs/optics/arrow-optics/api/arrow-optics.api
index aa6ac451a63..970a6993266 100644
--- a/arrow-libs/optics/arrow-optics/api/arrow-optics.api
+++ b/arrow-libs/optics/arrow-optics/api/arrow-optics.api
@@ -151,6 +151,9 @@ public final class arrow/optics/ListKt {
 	public static final fun unsnoc (Ljava/util/List;)Lkotlin/Pair;
 }
 
+public abstract interface annotation class arrow/optics/OpticsCopyMarker : java/lang/annotation/Annotation {
+}
+
 public final class arrow/optics/OptionalGetterKt {
 	public static final fun OptionalGetter (Lkotlin/jvm/functions/Function1;)Larrow/optics/POptionalGetter;
 }
diff --git a/arrow-libs/optics/arrow-optics/build.gradle.kts b/arrow-libs/optics/arrow-optics/build.gradle.kts
index 194b92b561a..999fbe82701 100644
--- a/arrow-libs/optics/arrow-optics/build.gradle.kts
+++ b/arrow-libs/optics/arrow-optics/build.gradle.kts
@@ -20,6 +20,10 @@ if (enableCompatibilityMetadataVariant) {
   }
 }
 
+tasks.withType<org.jetbrains.kotlin.gradle.tasks.KotlinCompile>().configureEach {
+  kotlinOptions.freeCompilerArgs += listOf("-Xenable-builder-inference", "-opt-in=kotlin.RequiresOptIn")
+}
+
 kotlin {
   sourceSets {
     commonMain {
diff --git a/arrow-libs/optics/arrow-optics/src/commonMain/kotlin/arrow/optics/Copy.kt b/arrow-libs/optics/arrow-optics/src/commonMain/kotlin/arrow/optics/Copy.kt
index 5b231df3623..87a21dfd257 100644
--- a/arrow-libs/optics/arrow-optics/src/commonMain/kotlin/arrow/optics/Copy.kt
+++ b/arrow-libs/optics/arrow-optics/src/commonMain/kotlin/arrow/optics/Copy.kt
@@ -1,5 +1,11 @@
 package arrow.optics
 
+import kotlin.experimental.ExperimentalTypeInference
+
+@DslMarker
+public annotation class OpticsCopyMarker
+
+@OpticsCopyMarker
 public interface Copy<A> {
   /**
    * Changes the value of the element(s) pointed by the [Setter].
@@ -33,7 +39,8 @@ public interface Copy<A> {
    * }
    * ```
    */
-  public fun <B> inside(field: Traversal<A, B>, f: Copy<B>.() -> Unit): Unit =
+  @OptIn(ExperimentalTypeInference::class)
+  public fun <B> inside(field: Traversal<A, B>, @BuilderInference f: Copy<B>.() -> Unit): Unit =
     field.transform { it.copy(f) }
 }
 
@@ -67,5 +74,6 @@ private class CopyImpl<A>(var current: A): Copy<A> {
  * }
  * ```
  */
-public fun <A> A.copy(f: Copy<A>.() -> Unit): A =
+@OptIn(ExperimentalTypeInference::class)
+public fun <A> A.copy(@BuilderInference f: Copy<A>.() -> Unit): A =
   CopyImpl(this).also(f).current

From 1ee8e7244ea5766d0f89b9ceb4bf5a850898eb6f Mon Sep 17 00:00:00 2001
From: Alejandro Serrano <trupill@gmail.com>
Date: Mon, 8 Aug 2022 10:05:22 +0200
Subject: [PATCH 2/3] Delete opt-in from the list of compiler options

---
 arrow-libs/optics/arrow-optics/build.gradle.kts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arrow-libs/optics/arrow-optics/build.gradle.kts b/arrow-libs/optics/arrow-optics/build.gradle.kts
index 999fbe82701..60e92cfdbbf 100644
--- a/arrow-libs/optics/arrow-optics/build.gradle.kts
+++ b/arrow-libs/optics/arrow-optics/build.gradle.kts
@@ -21,7 +21,7 @@ if (enableCompatibilityMetadataVariant) {
 }
 
 tasks.withType<org.jetbrains.kotlin.gradle.tasks.KotlinCompile>().configureEach {
-  kotlinOptions.freeCompilerArgs += listOf("-Xenable-builder-inference", "-opt-in=kotlin.RequiresOptIn")
+  kotlinOptions.freeCompilerArgs += listOf("-Xenable-builder-inference")
 }
 
 kotlin {

From 9a288990f34df1440464aa2bf38a373c77b95405 Mon Sep 17 00:00:00 2001
From: Alejandro Serrano <trupill@gmail.com>
Date: Mon, 8 Aug 2022 19:10:22 +0200
Subject: [PATCH 3/3] Remove all compiler args

---
 arrow-libs/optics/arrow-optics/build.gradle.kts | 4 ----
 1 file changed, 4 deletions(-)

diff --git a/arrow-libs/optics/arrow-optics/build.gradle.kts b/arrow-libs/optics/arrow-optics/build.gradle.kts
index 60e92cfdbbf..194b92b561a 100644
--- a/arrow-libs/optics/arrow-optics/build.gradle.kts
+++ b/arrow-libs/optics/arrow-optics/build.gradle.kts
@@ -20,10 +20,6 @@ if (enableCompatibilityMetadataVariant) {
   }
 }
 
-tasks.withType<org.jetbrains.kotlin.gradle.tasks.KotlinCompile>().configureEach {
-  kotlinOptions.freeCompilerArgs += listOf("-Xenable-builder-inference")
-}
-
 kotlin {
   sourceSets {
     commonMain {