feat: add MapConcurrent

slice/slice_example_test.go

@@ -1139,6 +1139,7 @@ func ExampleRandom() {
 	if idx >= 0 && idx < len(nums) && Contain(nums, val) {
 		fmt.Println("okk")
 	}
+
 	// Output:
 	// okk
 }
@@ -1148,6 +1149,7 @@ func ExampleSetToDefaultIf() {
 	modifiedStrs, count := SetToDefaultIf(strs, func(s string) bool { return "a" == s })
 	fmt.Println(modifiedStrs)
 	fmt.Println(count)
+
 	// Output:
 	// [ b  c d ]
 	// 3
@@ -1170,6 +1172,7 @@ func ExampleRightPadding() {
 	nums := []int{1, 2, 3, 4, 5}
 	padded := RightPadding(nums, 0, 3)
 	fmt.Println(padded)
+
 	// Output:
 	// [1 2 3 4 5 0 0 0]
 }
@@ -1178,6 +1181,7 @@ func ExampleLeftPadding() {
 	nums := []int{1, 2, 3, 4, 5}
 	padded := LeftPadding(nums, 0, 3)
 	fmt.Println(padded)
+
 	// Output:
 	// [0 0 0 1 2 3 4 5]
 }
@@ -1190,6 +1194,17 @@ func ExampleUniqueByParallel() {
 	result := UniqueByParallel(nums, numOfThreads, comparator)
 
 	fmt.Println(result)
+
 	// Output:
 	// [1 2 3 4 5 6 7]
 }
+
+func ExampleMapConcurrent() {
+	nums := []int{1, 2, 3, 4, 5, 6}
+	result := MapConcurrent(nums, 4, func(_, n int) int { return n * n })
+
+	fmt.Println(result)
+
+	// Output:
+	// [1 4 9 16 25 36]
+}

slice/slice_parallel.go

@@ -8,6 +8,33 @@ import (
 	"sync"
 )
 
+// MapConcurrent applies the iteratee function to each item in the slice by concrrent.
+// Play: todo
+func MapConcurrent[T any, U any](slice []T, numOfThreads int, iteratee func(index int, item T) U) []U {
+	result := make([]U, len(slice))
+	var wg sync.WaitGroup
+
+	workerChan := make(chan struct{}, numOfThreads)
+
+	for index, item := range slice {
+		wg.Add(1)
+
+		workerChan <- struct{}{}
+
+		go func(i int, v T) {
+			defer wg.Done()
+
+			result[i] = iteratee(i, v)
+
+			<-workerChan
+		}(index, item)
+	}
+
+	wg.Wait()
+
+	return result
+}
+
 // UniqueByParallel removes duplicate elements from the slice by parallel
 // The comparator function is used to compare the elements
 // The numOfThreads parameter specifies the number of threads to use

slice/slice_test.go

@@ -1516,3 +1516,29 @@ func TestUniqueByParallel(t *testing.T) {
 
 	assert.Equal([]int{1, 2, 3, 4, 5, 6, 7}, result)
 }
+
+func TestMapConcurrent(t *testing.T) {
+	t.Parallel()
+
+	assert := internal.NewAssert(t, "TestMapConcurrent")
+
+	t.Run("empty slice", func(t *testing.T) {
+		actual := MapConcurrent([]int{}, 4, func(_, n int) int { return n * n })
+		assert.Equal([]int{}, actual)
+	})
+
+	t.Run("single thread", func(t *testing.T) {
+		nums := []int{1, 2, 3, 4, 5, 6}
+		expected := []int{1, 4, 9, 16, 25, 36}
+		actual := MapConcurrent(nums, 1, func(_, n int) int { return n * n })
+		assert.Equal(expected, actual)
+	})
+
+	t.Run("multiple threads", func(t *testing.T) {
+		nums := []int{1, 2, 3, 4, 5, 6}
+		expected := []int{1, 4, 9, 16, 25, 36}
+		actual := MapConcurrent(nums, 4, func(_, n int) int { return n * n })
+		assert.Equal(expected, actual)
+	})
+
+}