Add toElement helper in ErasedProductInstances1

typelevel · Sep 15, 2022 · 96568d2 · 96568d2
1 parent e04a7cd
commit 96568d2
Showing 1 changed file with 17 additions and 16 deletions.
diff --git a/modules/deriving/src/main/scala/shapeless3/deriving/internals/erased.scala b/modules/deriving/src/main/scala/shapeless3/deriving/internals/erased.scala
@@ -56,6 +56,7 @@ private[shapeless3] final class ErasedProductInstances1[K, FT](val mirror: Mirro
   lazy val i = i0()
 
   inline def toProduct(x: Any): Product = x.asInstanceOf[Product]
+  private def toElement(x: Any) = toProduct(x).productElement(0)
   private def fromElement(x: Any) = mirror.fromProduct(Tuple1(x))
 
   final def erasedMapK(f: Any => Any): ErasedProductInstances[K, ?] =
@@ -78,45 +79,45 @@ private[shapeless3] final class ErasedProductInstances1[K, FT](val mirror: Mirro
     }
   }
 
-  final def erasedMap(x0: Any)(f: (Any, Any) => Any): Any =
-    fromElement(f(i, toProduct(x0).productElement(0)))
+  final def erasedMap(x: Any)(f: (Any, Any) => Any): Any =
+    fromElement(f(i, toElement(x)))
 
   final def erasedTraverse[F[_]](x: Any)(map: Map[F])(pure: Pure[F])(ap: Ap[F])(f: (Any, Any) => F[Any]): F[Any] =
-    map(f(i, toProduct(x).productElement(0)), fromElement)
+    map(f(i, toElement(x)), fromElement)
 
-  final def erasedMap2(x0: Any, y0: Any)(f: (Any, Any, Any) => Any): Any =
-    fromElement(f(i, toProduct(x0).productElement(0), toProduct(y0).productElement(0)))
+  final def erasedMap2(x: Any, y: Any)(f: (Any, Any, Any) => Any): Any =
+    fromElement(f(i, toElement(x), toElement(y)))
 
-  final def erasedFoldLeft(x0: Any)(a: Any)(f: (Any, Any, Any) => CompleteOr[Any]): Any = {
-    f(a, i, toProduct(x0).productElement(0)) match {
+  final def erasedFoldLeft(x: Any)(a: Any)(f: (Any, Any, Any) => CompleteOr[Any]): Any = {
+    f(a, i, toElement(x)) match {
       case Complete(r) => r
       case acc => acc
     }
   }
 
-  final def erasedFoldLeft2(x0: Any, y0: Any)(a: Any)(f: (Any, Any, Any, Any) => CompleteOr[Any]): Any = {
-    f(a, i, toProduct(x0).productElement(0), toProduct(y0).productElement(0)) match {
+  final def erasedFoldLeft2(x: Any, y: Any)(a: Any)(f: (Any, Any, Any, Any) => CompleteOr[Any]): Any = {
+    f(a, i, toElement(x), toElement(y)) match {
       case Complete(r) => r
       case acc => acc
     }
   }
 
-  final def erasedFoldRight(x0: Any)(a: Any)(f: (Any, Any, Any) => CompleteOr[Any]): Any = {
-    f(i, toProduct(x0).productElement(0), a) match {
+  final def erasedFoldRight(x: Any)(a: Any)(f: (Any, Any, Any) => CompleteOr[Any]): Any = {
+    f(i, toElement(x), a) match {
       case Complete(r) => r
       case acc => acc
     }
   }
 
-  final def erasedFoldRight2(x0: Any, y0: Any)(a: Any)(f: (Any, Any, Any, Any) => CompleteOr[Any]): Any = {
-    f(i, toProduct(x0).productElement(0), toProduct(y0).productElement(0), a) match {
+  final def erasedFoldRight2(x: Any, y: Any)(a: Any)(f: (Any, Any, Any, Any) => CompleteOr[Any]): Any = {
+    f(i, toElement(x), toElement(y), a) match {
       case Complete(r) => r
       case acc => acc
     }
   }
 
-  final def erasedProject(x0: Any)(p: Int)(f: (Any, Any) => Any): Any =
-    f(i, toProduct(x0).productElement(0))
+  final def erasedProject(x: Any)(p: Int)(f: (Any, Any) => Any): Any =
+    f(i, toElement(x))
 }
 
 object ErasedProductInstances1 {
@@ -139,7 +140,7 @@ private[shapeless3] final class ErasedProductInstancesN[K, FT](val mirror: Mirro
 
   private def traverseProduct[F[_]](x: Product, f: (Any, Any) => F[Any])(pure: Pure[F], map: Map[F], ap: Ap[F]): F[Any] =
     val n = is.length
-    if n == 0 then pure(x)
+    if n == 0 then pure(fromEmptyProduct)
     else
       var acc = pure(Vector.empty[Any])
       var i = 0