Implement QuicklensFunctor for Array (map[A, B] simplified to map[A])

softwaremill · Apr 28, 2022 · 56cc939 · 56cc939
1 parent 6c4c95e
commit 56cc939
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Showing 2 changed files with 14 additions and 6 deletions.
diff --git a/quicklens/src/main/scala-3/com/softwaremill/quicklens/package.scala b/quicklens/src/main/scala-3/com/softwaremill/quicklens/package.scala
@@ -3,6 +3,7 @@ package com.softwaremill
 import scala.collection.{Factory, SortedMap}
 import scala.annotation.compileTimeOnly
 import com.softwaremill.quicklens.QuicklensMacros._
+import scala.reflect.ClassTag
 
 package object quicklens {
 
@@ -127,27 +128,33 @@ package object quicklens {
   }
 
   trait QuicklensFunctor[F[_]] {
-    def map[A, B](fa: F[A], f: A => B): F[B]
+    def map[A](fa: F[A], f: A => A): F[A]
     def each[A](fa: F[A], f: A => A): F[A] = map(fa, f)
     def eachWhere[A](fa: F[A], f: A => A, cond: A => Boolean): F[A] = map(fa, x => if cond(x) then f(x) else x)
   }
 
   object QuicklensFunctor {
     given [S <: ([V] =>> Seq[V])]: QuicklensFunctor[S] with {
-      def map[A, B](fa: S[A], f: A => B): S[B] = fa.map(f).asInstanceOf[S[B]]
+      def map[A](fa: S[A], f: A => A): S[A] = fa.map(f).asInstanceOf[S[A]]
     }
 
     given QuicklensFunctor[Option] with {
-      def map[A, B](fa: Option[A], f: A => B): Option[B] = fa.map(f)
+      def map[A](fa: Option[A], f: A => A): Option[A] = fa.map(f)
+    }
+
+    given QuicklensFunctor[Array] with {
+      def map[A](fa: Array[A], f: A => A): Array[A] =
+        implicit val aClassTag: ClassTag[A] = fa.elemTag.asInstanceOf[ClassTag[A]]
+        fa.map(f)
     }
 
     given [K, M <: ([V] =>> Map[K, V])]: QuicklensFunctor[M] with {
-      def map[A, B](fa: M[A], f: A => B): M[B] = {
+      def map[A](fa: M[A], f: A => A): M[A] = {
         val mapped = fa.view.mapValues(f)
         (fa match {
           case sfa: SortedMap[K, A] => sfa.sortedMapFactory.from(mapped)(using sfa.ordering)
           case _                    => mapped.to(fa.mapFactory)
-        }).asInstanceOf[M[B]]
+        }).asInstanceOf[M[A]]
       }
     }
   }

diff --git a/quicklens/src/test/scala-3/com/softwaremill/quicklens/test/ModifyAllOptimizedTest.scala b/quicklens/src/test/scala-3/com/softwaremill/quicklens/test/ModifyAllOptimizedTest.scala
@@ -3,6 +3,7 @@ package com.softwaremill.quicklens
 import org.scalatest.flatspec.AnyFlatSpec
 import org.scalatest.BeforeAndAfterEach
 import org.scalatest.matchers.should.Matchers
+import scala.reflect.ClassTag
 
 class ModifyAllOptimizedTest extends AnyFlatSpec with Matchers with BeforeAndAfterEach {
   import ModifyAllOptimizedTest._
@@ -186,7 +187,7 @@ object ModifyAllOptimizedTest {
   }
 
   given QuicklensFunctor[Opt] with {
-    def map[A, B](fa: Opt[A], f: A => B): Opt[B] =
+    def map[A](fa: Opt[A], f: A => A): Opt[A] =
       Opt.eachCount = Opt.eachCount + 1
       fa match {
         case Nada => Nada