feat: add SliceToSet

README.md

@@ -101,6 +101,7 @@ Supported helpers for slices:
 - [RepeatBy](#repeatby)
 - [KeyBy](#keyby)
 - [Associate / SliceToMap](#associate-alias-slicetomap)
+- [SliceToSet](#slicetoset)
 - [Drop](#drop)
 - [DropRight](#dropright)
 - [DropWhile](#dropwhile)
@@ -728,6 +729,15 @@ aMap := lo.Associate(in, func (f *foo) (string, int) {
 
 [[play](https://go.dev/play/p/WHa2CfMO3Lr)]
 
+### SliceToSet
+
+Returns a map with each unique element of the slice as a key.
+
+```go
+set := lo.SliceToSet([]int{1, 1, 2, 3, 4})
+// map[int]struct{}{1:{}, 2:{}, 3:{}, 4:{}}
+```
+
 ### Drop
 
 Drops n elements from the beginning of a slice or array.

slice.go

@@ -378,6 +378,17 @@ func SliceToMap[T any, K comparable, V any](collection []T, transform func(item
 	return Associate(collection, transform)
 }
 
+// SliceToSet returns a map with each unique element of the slice as a key.
+func SliceToSet[T comparable, Slice ~[]T](collection Slice) map[T]struct{} {
+	result := make(map[T]struct{}, len(collection))
+
+	for _, item := range collection {
+		result[item] = struct{}{}
+	}
+
+	return result
+}
+
 // Drop drops n elements from the beginning of a slice or array.
 // Play: https://go.dev/play/p/JswS7vXRJP2
 func Drop[T any, Slice ~[]T](collection Slice, n int) Slice {

slice_example_test.go

@@ -88,6 +88,7 @@ func ExampleForEach() {
 	// 3
 	// 4
 }
+
 func ExampleForEachWhile() {
 	list := []int64{1, 2, -math.MaxInt, 4}
 
@@ -103,6 +104,7 @@ func ExampleForEachWhile() {
 	// 1
 	// 2
 }
+
 func ExampleTimes() {
 	result := Times(3, func(i int) string {
 		return strconv.FormatInt(int64(i), 10)
@@ -479,3 +481,19 @@ func ExampleIsSortedByKey() {
 
 	// Output: true
 }
+
+func ExampleSliceToSet() {
+	list := []string{"a", "a", "b", "b", "d"}
+
+	set := SliceToSet(list)
+	_, ok1 := set["a"]
+	_, ok2 := set["c"]
+	fmt.Printf("%v\n", ok1)
+	fmt.Printf("%v\n", ok2)
+	fmt.Printf("%v\n", set)
+
+	// Output:
+	// true
+	// false
+	// map[a:{} b:{} d:{}]
+}

slice_test.go

@@ -514,6 +514,18 @@ func TestSliceToMap(t *testing.T) {
 	}
 }
 
+func TestSliceToSet(t *testing.T) {
+	t.Parallel()
+	is := assert.New(t)
+
+	result1 := SliceToSet([]int{1, 2, 3, 4})
+	result2 := SliceToSet([]int{1, 1, 1, 2})
+	result3 := SliceToSet([]int{})
+	is.Equal(result1, map[int]struct{}{1: {}, 2: {}, 3: {}, 4: {}})
+	is.Equal(result2, map[int]struct{}{1: {}, 2: {}})
+	is.Equal(result3, map[int]struct{}{})
+}
+
 func TestDrop(t *testing.T) {
 	t.Parallel()
 	is := assert.New(t)