added more methods

Author: yadavan88

scala-core-modules/scala-core-numbers-2/src/main/scala/com/baeldung/scala/listsum/SumList.scala

@@ -33,4 +33,8 @@ object SumList {
     rec(list, 0)
   }
 
+  def sumNumeric[T](list: List[T])(using numeric: Numeric[T]): T = {
+    list.sum
+  }
+
 }

scala-core-modules/scala-core-numbers-2/src/test/scala/com/baeldung/scala/listsum/SumListUnitTest.scala

@@ -22,7 +22,7 @@ class SumListUnitTest
     ("sumByReduce()", SumList.sumByReduce),
     ("sumByIteration()", SumList.sumByIteration),
     ("sumByFor()", SumList.sumByFor),
-    ("sumByTailRecursion()", SumList.sumByTailRecursion),
+    ("sumByTailRecursion()", SumList.sumByTailRecursion)
   )
 
   it should "calculate sum for a list" in {
@@ -35,4 +35,23 @@ class SumListUnitTest
     }
   }
 
+  it should "calculate sum for any numeric types" in {
+    val ints = List(1, 2, 3, 4)
+    SumList.sumNumeric(ints) shouldBe 10
+    SumList.sumNumeric(List.empty[Int]) shouldBe 0
+
+    val doubles = List(1d, 2d, 3d, 4d)
+    SumList.sumNumeric(doubles) shouldBe 10d
+
+    val bigints = List(BigInt(1), BigInt(2), BigInt(3), BigInt(4))
+    SumList.sumNumeric(bigints) shouldBe BigInt(10)
+
+  }
+
+  it should "calculate the sum of inside fields" in {
+    case class Item(price: Int)
+    val items = List(Item(1), Item(2), Item(3), Item(4))
+    items.foldLeft(0)((acc, item) => acc + item.price) shouldBe 10
+  }
+
 }