doc: improve doc for lo.Sum

CHANGELOG.md

@@ -10,6 +10,7 @@ Adding:
 - lo.CountValues
 - lo.CountValuesBy
 - lo.MapEntries
+- lo.Sum
 - TupleX.Unpack()
 
 ## 1.31.0 (2022-10-06)

README.md

@@ -120,6 +120,7 @@ Supported math helpers:
 
 - [Range / RangeFrom / RangeWithSteps](#range--rangefrom--rangewithsteps)
 - [Clamp](#clamp)
+- [Sum](#sum)
 - [SumBy](#sumby)
 
 Supported helpers for strings:
@@ -1142,9 +1143,24 @@ r3 := lo.Clamp(42, -10, 10)
 
 [[play](https://go.dev/play/p/RU4lJNC2hlI)]
 
+### Sum
+
+Sums the values in a collection.
+
+If collection is empty 0 is returned.
+
+```go
+list := []int{1, 2, 3, 4, 5}
+sum := lo.Sum(list)
+// 15
+```
+
+[[play](https://go.dev/play/p/upfeJVqs4Bt)]
+
 ### SumBy
 
 Summarizes the values in a collection using the given return value from the iteration function.
+
 If collection is empty 0 is returned.
 
 ```go

math.go

@@ -63,21 +63,22 @@ func Clamp[T constraints.Ordered](value T, min T, max T) T {
 	return value
 }
 
-// SumBy summarizes the values in a collection using the given return value from the iteration function. If collection is empty 0 is returned.
-// Play: https://go.dev/play/p/Dz_a_7jN_ca
-func SumBy[T any, R constraints.Float | constraints.Integer](collection []T, iteratee func(T) R) R {
-	var sum R = 0
-	for _, item := range collection {
-		sum = sum + iteratee(item)
-	}
-	return sum
-}
-
-// Sums the values in a slice.
-func Sum[T constraints.Float | constraints.Integer](collection []T) T {
+// Sum sums the values in a collection. If collection is empty 0 is returned.
+// Play: https://go.dev/play/p/upfeJVqs4Bt
+func Sum[T constraints.Float | constraints.Integer | constraints.Complex](collection []T) T {
 	var sum T = 0
 	for _, val := range collection {
 		sum += val
 	}
 	return sum
 }
+
+// SumBy summarizes the values in a collection using the given return value from the iteration function. If collection is empty 0 is returned.
+// Play: https://go.dev/play/p/Dz_a_7jN_ca
+func SumBy[T any, R constraints.Float | constraints.Integer | constraints.Complex](collection []T, iteratee func(T) R) R {
+	var sum R = 0
+	for _, item := range collection {
+		sum = sum + iteratee(item)
+	}
+	return sum
+}

math_example_test.go

@@ -47,6 +47,15 @@ func ExampleClamp() {
 	// 10
 }
 
+func ExampleSum() {
+	list := []int{1, 2, 3, 4, 5}
+
+	sum := Sum(list)
+
+	fmt.Printf("%v", sum)
+	// Output: 15
+}
+
 func ExampleSumBy() {
 	list := []string{"foo", "bar"}
 

math_test.go

@@ -65,6 +65,22 @@ func TestClamp(t *testing.T) {
 	is.Equal(result3, 10)
 }
 
+func TestSum(t *testing.T) {
+	is := assert.New(t)
+
+	result1 := Sum([]float32{2.3, 3.3, 4, 5.3})
+	result2 := Sum([]int32{2, 3, 4, 5})
+	result3 := Sum([]uint32{2, 3, 4, 5})
+	result4 := Sum([]uint32{})
+	result5 := Sum([]complex128{4_4, 2_2})
+
+	is.Equal(result1, float32(14.900001))
+	is.Equal(result2, int32(14))
+	is.Equal(result3, uint32(14))
+	is.Equal(result4, uint32(0))
+	is.Equal(result5, complex128(6_6))
+}
+
 func TestSumBy(t *testing.T) {
 	t.Parallel()
 	is := assert.New(t)
@@ -73,23 +89,11 @@ func TestSumBy(t *testing.T) {
 	result2 := SumBy([]int32{2, 3, 4, 5}, func(n int32) int32 { return n })
 	result3 := SumBy([]uint32{2, 3, 4, 5}, func(n uint32) uint32 { return n })
 	result4 := SumBy([]uint32{}, func(n uint32) uint32 { return n })
+	result5 := SumBy([]complex128{4_4, 2_2}, func(n complex128) complex128 { return n })
 
 	is.Equal(result1, float32(14.900001))
 	is.Equal(result2, int32(14))
 	is.Equal(result3, uint32(14))
 	is.Equal(result4, uint32(0))
-}
-
-func TestSum(t *testing.T) {
-	is := assert.New(t)
-
-	result1 := Sum([]float32{2.3, 3.3, 4, 5.3})
-	result2 := Sum([]int32{2, 3, 4, 5})
-	result3 := Sum([]uint32{2, 3, 4, 5})
-	result4 := Sum([]uint32{})
-
-	is.Equal(result1, float32(14.900001))
-	is.Equal(result2, int32(14))
-	is.Equal(result3, uint32(14))
-	is.Equal(result4, uint32(0))
+	is.Equal(result5, complex128(6_6))
 }