release v2.0.3

README.md

@@ -4,7 +4,7 @@
 <br/>
 
 ![Go version](https://img.shields.io/badge/go-%3E%3D1.16<recommend>-9cf)
-[![Release](https://img.shields.io/badge/release-2.0.2-green.svg)](https://github.com/duke-git/lancet/releases)
+[![Release](https://img.shields.io/badge/release-2.0.3-green.svg)](https://github.com/duke-git/lancet/releases)
 [![GoDoc](https://godoc.org/github.com/duke-git/lancet/v2?status.svg)](https://pkg.go.dev/github.com/duke-git/lancet/v2)
 [![Go Report Card](https://goreportcard.com/badge/github.com/duke-git/lancet/v2)](https://goreportcard.com/report/github.com/duke-git/lancet/v2)
 [![test](https://github.com/duke-git/lancet/actions/workflows/codecov.yml/badge.svg?branch=main&event=push)](https://github.com/duke-git/lancet/actions/workflows/codecov.yml)
@@ -230,6 +230,22 @@ import "github.com/duke-git/lancet/v2/function"
 - [Watcher](https://github.com/duke-git/lancet/blob/main/docs/function.md#Watcher)
 
 
+### Maputil package includes some functions to manipulate map.
+
+```go
+import "github.com/duke-git/lancet/v2/maputil"
+```
+
+#### Function list:
+- [ForEach](https://github.com/duke-git/lancet/blob/main/docs/maputil.md#ForEach)
+- [Filter](https://github.com/duke-git/lancet/blob/main/docs/maputil.md#Filter)
+- [Intersect](https://github.com/duke-git/lancet/blob/main/docs/maputil.md#Intersect)
+- [Keys](https://github.com/duke-git/lancet/blob/main/docs/maputil.md#Keys)
+- [Merge](https://github.com/duke-git/lancet/blob/main/docs/maputil.md#Merge)
+- [Minus](https://github.com/duke-git/lancet/blob/main/docs/maputil.md#Minus)
+- [Values](https://github.com/duke-git/lancet/blob/main/docs/maputil.md#Values)
+
+
 ### Mathutil package implements some functions for math calculation.
 
 ```go
@@ -331,6 +347,7 @@ import "github.com/duke-git/lancet/v2/slice"
 - [SortByField](https://github.com/duke-git/lancet/blob/main/docs/slice.md#SortByField)
 - [Some](https://github.com/duke-git/lancet/blob/main/docs/slice.md#Some)
 - [StringSlice](https://github.com/duke-git/lancet/blob/main/docs/slice.md#StringSlice)
+- [SymmetricDifference](https://github.com/duke-git/lancet/blob/main/docs/slice.md#SymmetricDifference)
 - [Unique](https://github.com/duke-git/lancet/blob/main/docs/slice.md#Unique)
 - [Union](https://github.com/duke-git/lancet/blob/main/docs/slice.md#Union)
 - [UpdateAt](https://github.com/duke-git/lancet/blob/main/docs/slice.md#UpdateAt)

README_zh-CN.md

@@ -4,7 +4,7 @@
 <br/>
 
 ![Go version](https://img.shields.io/badge/go-%3E%3D1.16<recommend>-9cf)
-[![Release](https://img.shields.io/badge/release-2.0.2-green.svg)](https://github.com/duke-git/lancet/releases)
+[![Release](https://img.shields.io/badge/release-2.0.3-green.svg)](https://github.com/duke-git/lancet/releases)
 [![GoDoc](https://godoc.org/github.com/duke-git/lancet/v2?status.svg)](https://pkg.go.dev/github.com/duke-git/lancet/v2)
 [![Go Report Card](https://goreportcard.com/badge/github.com/duke-git/lancet/v2)](https://goreportcard.com/report/github.com/duke-git/lancet/v2)
 [![test](https://github.com/duke-git/lancet/actions/workflows/codecov.yml/badge.svg?branch=main&event=push)](https://github.com/duke-git/lancet/actions/workflows/codecov.yml)
@@ -229,6 +229,22 @@ import "github.com/duke-git/lancet/v2/function"
 - [Delay](https://github.com/duke-git/lancet/blob/main/docs/function_zh-CN.md#Delay)
 - [Watcher](https://github.com/duke-git/lancet/blob/main/docs/function_zh-CN.md#Watcher)
 
+
+### maputil包包括一些操作map的函数.
+
+```go
+import "github.com/duke-git/lancet/v2/maputil"
+```
+
+#### 函数列表:
+- [ForEach](https://github.com/duke-git/lancet/blob/main/docs/maputil_zh-CN.md#ForEach)
+- [Filter](https://github.com/duke-git/lancet/blob/main/docs/maputil_zh-CN.md#Filter)
+- [Intersect](https://github.com/duke-git/lancet/blob/main/docs/maputil_zh-CN.md#Intersect)
+- [Keys](https://github.com/duke-git/lancet/blob/main/docs/maputil_zh-CN.md#Keys)
+- [Merge](https://github.com/duke-git/lancet/blob/main/docs/maputil_zh-CN.md#Merge)
+- [Minus](https://github.com/duke-git/lancet/blob/main/docs/maputil_zh-CN.md#Minus)
+- [Values](https://github.com/duke-git/lancet/blob/main/docs/maputil_zh-CN.md#Values)
+
 ### mathutil包实现了一些数学计算的函数。
 
 ```go
@@ -329,6 +345,7 @@ import "github.com/duke-git/lancet/v2/slice"
 - [SortByField](https://github.com/duke-git/lancet/blob/main/docs/slice_zh-CN.md#SortByField)
 - [Some](https://github.com/duke-git/lancet/blob/main/docs/slice_zh-CN.md#Some)
 - [StringSlice](https://github.com/duke-git/lancet/blob/main/docs/slice_zh-CN.md#StringSlice)
+- [SymmetricDifference](https://github.com/duke-git/lancet/blob/main/docs/slice_zh-CN.md#SymmetricDifference)
 - [Unique](https://github.com/duke-git/lancet/blob/main/docs/slice_zh-CN.md#Unique)
 - [Union](https://github.com/duke-git/lancet/blob/main/docs/slice_zh-CN.md#Union)
 - [UpdateAt](https://github.com/duke-git/lancet/blob/main/docs/slice_zh-CN.md#UpdateAt)

datastructure/set/set.go

@@ -103,3 +103,34 @@ func (s Set[T]) Intersection(other Set[T]) Set[T] {
 
 	return set
 }
+
+// SymmetricDifference creates a new set whose element is in set1 or set2, but not in both sets
+func (s Set[T]) SymmetricDifference(other Set[T]) Set[T] {
+	set := NewSet[T]()
+	s.Iterate(func(value T) {
+		if !other.Contain(value) {
+			set.Add(value)
+		}
+	})
+
+	other.Iterate(func(value T) {
+		if !s.Contain(value) {
+			set.Add(value)
+		}
+	})
+
+	return set
+}
+
+// Minus creates an set of whose element in origin set but not in compared set
+func (s Set[T]) Minus(comparedSet Set[T]) Set[T] {
+	set := NewSet[T]()
+
+	s.Iterate(func(value T) {
+		if !comparedSet.Contain(value) {
+			set.Add(value)
+		}
+	})
+
+	return set
+}

datastructure/set/set_test.go

@@ -127,3 +127,23 @@ func TestSet_Intersection(t *testing.T) {
 
 	assert.Equal(expected, intersectionSet)
 }
+
+func TestSet_SymmetricDifference(t *testing.T) {
+	assert := internal.NewAssert(t, "TestSet_SymmetricDifference")
+
+	set1 := NewSet(1, 2, 3)
+	set2 := NewSet(2, 3, 4, 5)
+
+	assert.Equal(NewSet(1, 4, 5), set1.SymmetricDifference(set2))
+}
+
+func TestSet_Minus(t *testing.T) {
+	assert := internal.NewAssert(t, "TestSet_Minus")
+
+	set1 := NewSet(1, 2, 3)
+	set2 := NewSet(2, 3, 4, 5)
+	set3 := NewSet(2, 3)
+
+	assert.Equal(NewSet(1), set1.Minus(set2))
+	assert.Equal(NewSet(4, 5), set2.Minus(set3))
+}

docs/maputil.md

@@ -0,0 +1,304 @@
+# Maputil
+Package maputil includes some functions to manipulate map.
+
+<div STYLE="page-break-after: always;"></div>
+
+## Source:
+
+- [https://github.com/duke-git/lancet/blob/main/maputil/maputil.go](https://github.com/duke-git/lancet/blob/main/maputil/maputil.go)
+
+
+<div STYLE="page-break-after: always;"></div>
+
+## Example:
+```go
+import (
+    "github.com/duke-git/lancet/v2/maputil"
+)
+```
+
+<div STYLE="page-break-after: always;"></div>
+
+## Index
+- [ForEach](#ForEach)
+- [Filter](#Filter)
+- [Intersect](#Intersect)
+- [Keys](#Keys)
+- [Merge](#Merge)
+- [Minus](#Minus)
+- [Values](#Values)
+
+<div STYLE="page-break-after: always;"></div>
+
+## Documentation
+
+
+
+### <span id="ForEach">ForEach</span>
+<p>Executes iteratee funcation for every key and value pair in map.</p>
+
+<b>Signature:</b>
+
+```go
+func ForEach[K comparable, V any](m map[K]V, iteratee func(key K, value V))
+```
+<b>Example:</b>
+
+```go
+package main
+
+import (
+    "fmt"
+    "github.com/duke-git/lancet/v2/maputil"
+)
+
+func main() {
+	m := map[string]int{
+		"a": 1,
+		"b": 2,
+		"c": 3,
+		"d": 4,
+	}
+
+	var sum int
+
+	maputil.ForEach(m, func(_ string, value int) {
+		sum += value
+	})
+	fmt.Println(sum) // 10
+}
+```
+
+
+
+
+### <span id="Filter">Filter</span>
+<p>Iterates over map, return a new map contains all key and value pairs pass the predicate function.</p>
+
+<b>Signature:</b>
+
+```go
+func Filter[K comparable, V any](m map[K]V, predicate func(key K, value V) bool) map[K]V
+```
+<b>Example:</b>
+
+```go
+package main
+
+import (
+    "fmt"
+    "github.com/duke-git/lancet/v2/maputil"
+)
+
+func main() {
+	m := map[string]int{
+		"a": 1,
+		"b": 2,
+		"c": 3,
+		"d": 4,
+		"e": 5,
+	}
+	isEven := func(_ string, value int) bool {
+		return value%2 == 0
+	}
+
+	maputil.Filter(m, func(_ string, value int) {
+		sum += value
+	})
+	res := maputil.Filter(m, isEven)
+	fmt.Println(res) // map[string]int{"b": 2, "d": 4,}
+}
+```
+
+
+
+
+### <span id="Intersect">Intersect</span>
+<p>Iterates over maps, return a new map of key and value pairs in all given maps.</p>
+
+<b>Signature:</b>
+
+```go
+func Intersect[K comparable, V any](maps ...map[K]V) map[K]V
+```
+<b>Example:</b>
+
+```go
+package main
+
+import (
+    "fmt"
+    "github.com/duke-git/lancet/v2/maputil"
+)
+
+func main() {
+	m1 := map[string]int{
+		"a": 1,
+		"b": 2,
+		"c": 3,
+	}
+
+	m2 := map[string]int{
+		"a": 1,
+		"b": 2,
+		"c": 6,
+		"d": 7,
+	}
+
+	m3 := map[string]int{
+		"a": 1,
+		"b": 9,
+		"e": 9,
+	}
+
+	fmt.Println(maputil.Intersect(m1)) // map[string]int{"a": 1, "b": 2, "c": 3}
+
+	fmt.Println(maputil.Intersect(m1, m2)) // map[string]int{"a": 1, "b": 2}
+
+	fmt.Println(maputil.Intersect(m1, m2, m3)) // map[string]int{"a": 1}
+}
+```
+
+
+
+
+### <span id="Keys">Keys</span>
+<p>Returns a slice of the map's keys.</p>
+
+<b>Signature:</b>
+
+```go
+func Keys[K comparable, V any](m map[K]V) []K
+```
+<b>Example:</b>
+
+```go
+package main
+
+import (
+    "fmt"
+    "github.com/duke-git/lancet/v2/maputil"
+)
+
+func main() {
+	m := map[int]string{
+		1: "a",
+		2: "a",
+		3: "b",
+		4: "c",
+		5: "d",
+	}
+
+	keys := maputil.Keys(m)
+	sort.Ints(keys)
+	fmt.Println(keys) // []int{1, 2, 3, 4, 5}
+}
+```
+
+
+
+
+### <span id="Merge">Merge</span>
+<p>Merge maps, next key will overwrite previous key.</p>
+
+<b>Signature:</b>
+
+```go
+func Merge[K comparable, V any](maps ...map[K]V) map[K]V
+```
+<b>Example:</b>
+
+```go
+package main
+
+import (
+    "fmt"
+    "github.com/duke-git/lancet/v2/maputil"
+)
+
+func main() {
+	m1 := map[int]string{
+		1: "a",
+		2: "b",
+	}
+	m2 := map[int]string{
+		1: "1",
+		3: "2",
+	}
+	fmt.Println(maputil.Merge(m1, m2)) // map[int]string{1:"1", 2:"b", 3:"2",}
+}
+```
+
+
+
+
+### <span id="Minus">Minus</span>
+<p>Creates an map of whose key in mapA but not in mapB.</p>
+
+<b>Signature:</b>
+
+```go
+func Minus[K comparable, V any](mapA, mapB map[K]V) map[K]V
+```
+<b>Example:</b>
+
+```go
+package main
+
+import (
+    "fmt"
+    "github.com/duke-git/lancet/v2/maputil"
+)
+
+func main() {
+	m1 := map[string]int{
+		"a": 1,
+		"b": 2,
+		"c": 3,
+	}
+
+	m2 := map[string]int{
+		"a": 11,
+		"b": 22,
+		"d": 33,
+	}
+
+	fmt.Println(maputil.Minus(m1, m2)) //map[string]int{"c": 3}
+}
+```
+
+
+
+### <span id="Values">Values</span>
+<p>Returns a slice of the map's values.</p>
+
+<b>Signature:</b>
+
+```go
+func Values[K comparable, V any](m map[K]V) []V
+```
+<b>Example:</b>
+
+```go
+package main
+
+import (
+    "fmt"
+    "github.com/duke-git/lancet/v2/maputil"
+)
+
+func main() {
+	m := map[int]string{
+		1: "a",
+		2: "a",
+		3: "b",
+		4: "c",
+		5: "d",
+	}
+
+	values := maputil.Values(m)
+	sort.Strings(values)
+
+	fmt.Println(values) // []string{"a", "a", "b", "c", "d"}
+}
+```

docs/maputil_zh-CN.md

@@ -0,0 +1,304 @@
+# Maputil
+maputil包包括一些操作map的函数。
+
+<div STYLE="page-break-after: always;"></div>
+
+## 源码:
+
+- [https://github.com/duke-git/lancet/blob/main/maputil/maputil.go](https://github.com/duke-git/lancet/blob/main/maputil/maputil.go)
+
+
+<div STYLE="page-break-after: always;"></div>
+
+## 用法:
+```go
+import (
+    "github.com/duke-git/lancet/v2/maputil"
+)
+```
+
+<div STYLE="page-break-after: always;"></div>
+
+## 目录:
+- [ForEach](#ForEach)
+- [Filter](#Filter)
+- [Intersect](#Intersect)
+- [Keys](#Keys)
+- [Merge](#Merge)
+- [Minus](#Minus)
+- [Values](#Values)
+
+<div STYLE="page-break-after: always;"></div>
+
+## API文档:
+
+
+
+### <span id="ForEach">ForEach</span>
+<p>对map中的每对key和value执行iteratee函数</p>
+
+<b>函数签名:</b>
+
+```go
+func ForEach[K comparable, V any](m map[K]V, iteratee func(key K, value V))
+```
+<b>例子:</b>
+
+```go
+package main
+
+import (
+    "fmt"
+    "github.com/duke-git/lancet/v2/maputil"
+)
+
+func main() {
+	m := map[string]int{
+		"a": 1,
+		"b": 2,
+		"c": 3,
+		"d": 4,
+	}
+
+	var sum int
+
+	maputil.ForEach(m, func(_ string, value int) {
+		sum += value
+	})
+	fmt.Println(sum) // 10
+}
+```
+
+
+
+
+### <span id="Filter">Filter</span>
+<p>迭代map中的每对key和value, 返回符合predicate函数的key, value</p>
+
+<b>函数签名:</b>
+
+```go
+func Filter[K comparable, V any](m map[K]V, predicate func(key K, value V) bool) map[K]V
+```
+<b>例子:</b>
+
+```go
+package main
+
+import (
+    "fmt"
+    "github.com/duke-git/lancet/v2/maputil"
+)
+
+func main() {
+	m := map[string]int{
+		"a": 1,
+		"b": 2,
+		"c": 3,
+		"d": 4,
+		"e": 5,
+	}
+	isEven := func(_ string, value int) bool {
+		return value%2 == 0
+	}
+
+	maputil.Filter(m, func(_ string, value int) {
+		sum += value
+	})
+	res := maputil.Filter(m, isEven)
+	fmt.Println(res) // map[string]int{"b": 2, "d": 4,}
+}
+```
+
+
+
+
+### <span id="Intersect">Intersect</span>
+<p>多个map的交集操作</p>
+
+<b>函数签名:</b>
+
+```go
+func Intersect[K comparable, V any](maps ...map[K]V) map[K]V
+```
+<b>例子:</b>
+
+```go
+package main
+
+import (
+    "fmt"
+    "github.com/duke-git/lancet/v2/maputil"
+)
+
+func main() {
+	m1 := map[string]int{
+		"a": 1,
+		"b": 2,
+		"c": 3,
+	}
+
+	m2 := map[string]int{
+		"a": 1,
+		"b": 2,
+		"c": 6,
+		"d": 7,
+	}
+
+	m3 := map[string]int{
+		"a": 1,
+		"b": 9,
+		"e": 9,
+	}
+
+	fmt.Println(maputil.Intersect(m1)) // map[string]int{"a": 1, "b": 2, "c": 3}
+
+	fmt.Println(maputil.Intersect(m1, m2)) // map[string]int{"a": 1, "b": 2}
+
+	fmt.Println(maputil.Intersect(m1, m2, m3)) // map[string]int{"a": 1}
+}
+```
+
+
+
+
+### <span id="Keys">Keys</span>
+<p>返回map中所有key的切片</p>
+
+<b>函数签名:</b>
+
+```go
+func Keys[K comparable, V any](m map[K]V) []K
+```
+<b>例子:</b>
+
+```go
+package main
+
+import (
+    "fmt"
+    "github.com/duke-git/lancet/v2/maputil"
+)
+
+func main() {
+	m := map[int]string{
+		1: "a",
+		2: "a",
+		3: "b",
+		4: "c",
+		5: "d",
+	}
+
+	keys := maputil.Keys(m)
+	sort.Ints(keys)
+	fmt.Println(keys) // []int{1, 2, 3, 4, 5}
+}
+```
+
+
+
+
+### <span id="Merge">Merge</span>
+<p>合并多个maps, 相同的key会被后来的key覆盖</p>
+
+<b>函数签名:</b>
+
+```go
+func Merge[K comparable, V any](maps ...map[K]V) map[K]V
+```
+<b>例子:</b>
+
+```go
+package main
+
+import (
+    "fmt"
+    "github.com/duke-git/lancet/v2/maputil"
+)
+
+func main() {
+	m1 := map[int]string{
+		1: "a",
+		2: "b",
+	}
+	m2 := map[int]string{
+		1: "1",
+		3: "2",
+	}
+	fmt.Println(maputil.Merge(m1, m2)) // map[int]string{1:"1", 2:"b", 3:"2",}
+}
+```
+
+
+
+
+### <span id="Minus">Minus</span>
+<p>返回一个map，其中的key存在于mapA，不存在于mapB.</p>
+
+<b>函数签名:</b>
+
+```go
+func Minus[K comparable, V any](mapA, mapB map[K]V) map[K]V
+```
+<b>例子:</b>
+
+```go
+package main
+
+import (
+    "fmt"
+    "github.com/duke-git/lancet/v2/maputil"
+)
+
+func main() {
+	m1 := map[string]int{
+		"a": 1,
+		"b": 2,
+		"c": 3,
+	}
+
+	m2 := map[string]int{
+		"a": 11,
+		"b": 22,
+		"d": 33,
+	}
+
+	fmt.Println(maputil.Minus(m1, m2)) //map[string]int{"c": 3}
+}
+```
+
+
+
+### <span id="Values">Values</span>
+<p>返回map中所有value的切片</p>
+
+<b>函数签名:</b>
+
+```go
+func Values[K comparable, V any](m map[K]V) []V
+```
+<b>例子:</b>
+
+```go
+package main
+
+import (
+    "fmt"
+    "github.com/duke-git/lancet/v2/maputil"
+)
+
+func main() {
+	m := map[int]string{
+		1: "a",
+		2: "a",
+		3: "b",
+		4: "c",
+		5: "d",
+	}
+
+	values := maputil.Values(m)
+	sort.Strings(values)
+
+	fmt.Println(values) // []string{"a", "a", "b", "c", "d"}
+}
+```

docs/slice.md

@@ -51,6 +51,7 @@ import (
 - [SortByField](#SortByField)
 - [Some](#Some)
 - [StringSlice](#StringSlice)
+- [SymmetricDifference](#SymmetricDifference)
 - [Unique](#Unique)
 - [Union](#Union)
 - [UpdateAt](#UpdateAt)
@@ -909,6 +910,35 @@ func main() {
 
 
 
+### <span id="SymmetricDifference">SymmetricDifference</span>
+<p>Create a slice whose element is in given slices, but not in both slices.</p>
+
+<b>Signature:</b>
+
+```go
+func SymmetricDifference[T any](slices ...[]T) []T
+```
+<b>Example:</b>
+
+```go
+import (
+	"fmt"
+	"github.com/duke-git/lancet/v2/slice"
+)
+
+func main() {
+	s1 := []int{1, 2, 3}
+	s2 := []int{1, 2, 4}
+	s3 := []int{1, 2, 3, 5}
+
+	fmt.Println(slice.SymmetricDifference(s1)) //[]int{1, 2, 3}
+	fmt.Println(slice.SymmetricDifference(s1, s2)) //[]int{3, 4}
+	fmt.Println(slice.SymmetricDifference(s1, s2, s3)) //[]int{3, 4, 5}
+}
+```
+
+
+
 ### <span id="Unique">Unique</span>
 <p>Remove duplicate elements in slice.</p>
 

docs/slice_zh-CN.md

@@ -51,6 +51,7 @@ import (
 - [SortByField](#SortByField)
 - [Some](#Some)
 - [StringSlice](#StringSlice)
+- [SymmetricDifference](#SymmetricDifference)
 - [Unique](#Unique)
 - [Union](#Union)
 - [UpdateAt](#UpdateAt)
@@ -909,6 +910,34 @@ func main() {
 
 
 
+### <span id="SymmetricDifference">SymmetricDifference</span>
+<p>返回一个切片，其中的元素存在于参数切片中，但不同时存储在于参数切片中（交集取反）</p>
+
+<b>函数签名:</b>
+
+```go
+func SymmetricDifference[T any](slices ...[]T) []T
+```
+<b>例子:</b>
+
+```go
+import (
+	"fmt"
+	"github.com/duke-git/lancet/v2/slice"
+)
+
+func main() {
+	s1 := []int{1, 2, 3}
+	s2 := []int{1, 2, 4}
+	s3 := []int{1, 2, 3, 5}
+
+	fmt.Println(slice.SymmetricDifference(s1)) //[]int{1, 2, 3}
+	fmt.Println(slice.SymmetricDifference(s1, s2)) //[]int{3, 4}
+	fmt.Println(slice.SymmetricDifference(s1, s2, s3)) //[]int{3, 4, 5}
+}
+```
+
+
 ### <span id="Unique">Unique</span>
 <p>删除切片中的重复元素</p>
 

maputil/map.go

@@ -0,0 +1,107 @@
+// Copyright 2021 dudaodong@gmail.com. All rights reserved.
+// Use of this source code is governed by MIT license
+
+// Package maputil includes some functions to manipulate map.
+package maputil
+
+import "reflect"
+
+// Keys returns a slice of the map's keys
+func Keys[K comparable, V any](m map[K]V) []K {
+	keys := make([]K, 0, len(m))
+
+	for k := range m {
+		keys = append(keys, k)
+	}
+
+	return keys
+}
+
+// Values returns a slice of the map's values
+func Values[K comparable, V any](m map[K]V) []V {
+	values := make([]V, 0, len(m))
+
+	for _, v := range m {
+		values = append(values, v)
+	}
+
+	return values
+}
+
+// Merge maps, next key will overwrite previous key
+func Merge[K comparable, V any](maps ...map[K]V) map[K]V {
+	res := make(map[K]V, 0)
+
+	for _, m := range maps {
+		for k, v := range m {
+			res[k] = v
+		}
+	}
+
+	return res
+}
+
+// ForEach executes iteratee funcation for every key and value pair in map
+func ForEach[K comparable, V any](m map[K]V, iteratee func(key K, value V)) {
+	for k, v := range m {
+		iteratee(k, v)
+	}
+}
+
+// Filter iterates over map, return a new map contains all key and value pairs pass the predicate function
+func Filter[K comparable, V any](m map[K]V, predicate func(key K, value V) bool) map[K]V {
+	res := make(map[K]V)
+
+	for k, v := range m {
+		if predicate(k, v) {
+			res[k] = v
+		}
+	}
+	return res
+}
+
+// Intersect iterates over maps, return a new map of key and value pairs in all given maps
+func Intersect[K comparable, V any](maps ...map[K]V) map[K]V {
+	if len(maps) == 0 {
+		return map[K]V{}
+	}
+	if len(maps) == 1 {
+		return maps[0]
+	}
+
+	res := make(map[K]V)
+
+	reducer := func(m1, m2 map[K]V) map[K]V {
+		m := make(map[K]V)
+		for k, v1 := range m1 {
+			if v2, ok := m2[k]; ok && reflect.DeepEqual(v1, v2) {
+				m[k] = v1
+			}
+		}
+		return m
+	}
+
+	reduceMaps := make([]map[K]V, 2, 2)
+	res = reducer(maps[0], maps[1])
+
+	for i := 2; i < len(maps); i++ {
+		reduceMaps[0] = res
+		reduceMaps[1] = maps[i]
+		res = reducer(reduceMaps[0], reduceMaps[1])
+	}
+
+	return res
+}
+
+
+// Minus creates an map of whose key in mapA but not in mapB
+func Minus[K comparable, V any](mapA, mapB map[K]V) map[K]V {
+	res := make(map[K]V)
+
+	for k, v := range mapA {
+		if _, ok := mapB[k]; !ok {
+			res[k] = v
+		}
+	}
+	return res
+}

maputil/map_test.go

@@ -0,0 +1,150 @@
+package maputil
+
+import (
+	"sort"
+	"testing"
+
+	"github.com/duke-git/lancet/v2/internal"
+)
+
+func TestKeys(t *testing.T) {
+	assert := internal.NewAssert(t, "TestKeys")
+
+	m := map[int]string{
+		1: "a",
+		2: "a",
+		3: "b",
+		4: "c",
+		5: "d",
+	}
+
+	keys := Keys(m)
+	sort.Ints(keys)
+
+	assert.Equal([]int{1, 2, 3, 4, 5}, keys)
+}
+
+func TestValues(t *testing.T) {
+	assert := internal.NewAssert(t, "TestValues")
+
+	m := map[int]string{
+		1: "a",
+		2: "a",
+		3: "b",
+		4: "c",
+		5: "d",
+	}
+
+	values := Values(m)
+	sort.Strings(values)
+
+	assert.Equal([]string{"a", "a", "b", "c", "d"}, values)
+}
+
+func TestMerge(t *testing.T) {
+	assert := internal.NewAssert(t, "TestMerge")
+
+	m1 := map[int]string{
+		1: "a",
+		2: "b",
+	}
+	m2 := map[int]string{
+		1: "1",
+		3: "2",
+	}
+
+	expected := map[int]string{
+		1: "1",
+		2: "b",
+		3: "2",
+	}
+	acturl := Merge(m1, m2)
+
+	assert.Equal(expected, acturl)
+}
+
+func TestForEach(t *testing.T) {
+	assert := internal.NewAssert(t, "TestForEach")
+
+	m := map[string]int{
+		"a": 1,
+		"b": 2,
+		"c": 3,
+		"d": 4,
+	}
+
+	var sum int
+
+	ForEach(m, func(_ string, value int) {
+		sum += value
+	})
+
+	assert.Equal(10, sum)
+}
+
+func TestFilter(t *testing.T) {
+	assert := internal.NewAssert(t, "TestFilter")
+
+	m := map[string]int{
+		"a": 1,
+		"b": 2,
+		"c": 3,
+		"d": 4,
+		"e": 5,
+	}
+	isEven := func(_ string, value int) bool {
+		return value%2 == 0
+	}
+
+	acturl := Filter(m, isEven)
+
+	assert.Equal(map[string]int{
+		"b": 2,
+		"d": 4,
+	}, acturl)
+}
+
+func TestIntersect(t *testing.T) {
+	assert := internal.NewAssert(t, "TestIntersect")
+
+	m1 := map[string]int{
+		"a": 1,
+		"b": 2,
+		"c": 3,
+	}
+
+	m2 := map[string]int{
+		"a": 1,
+		"b": 2,
+		"c": 6,
+		"d": 7,
+	}
+
+	m3 := map[string]int{
+		"a": 1,
+		"b": 9,
+		"e": 9,
+	}
+
+	assert.Equal(map[string]int{"a": 1, "b": 2, "c": 3}, Intersect(m1))
+	assert.Equal(map[string]int{"a": 1, "b": 2}, Intersect(m1, m2))
+	assert.Equal(map[string]int{"a": 1}, Intersect(m1, m2, m3))
+}
+
+func TestMinus(t *testing.T) {
+	assert := internal.NewAssert(t, "TestMinus")
+
+	m1 := map[string]int{
+		"a": 1,
+		"b": 2,
+		"c": 3,
+	}
+
+	m2 := map[string]int{
+		"a": 11,
+		"b": 22,
+		"d": 33,
+	}
+
+	assert.Equal(map[string]int{"c": 3}, Minus(m1, m2))
+}

slice/slice.go

@@ -571,7 +571,6 @@ func Union[T any](slices ...[]T) []T {
 
 // Intersection creates a slice of unique values that included by all slices.
 func Intersection[T any](slices ...[]T) []T {
-	var res []T
 	if len(slices) == 0 {
 		return []T{}
 	}
@@ -579,28 +578,51 @@ func Intersection[T any](slices ...[]T) []T {
 		return Unique(slices[0])
 	}
 
-	//return elements both in slice1 and slice2
+	var res []T
-	reduceFunc := func(slice1, slice2 []T) []T {
+
+	reducer := func(s1, s2 []T) []T {
 		s := make([]T, 0, 0)
-		for _, v := range slice1 {
+		for _, v := range s1 {
-			if Contain(slice2, v) {
+			if Contain(s2, v) {
 				s = append(s, v)
 			}
 		}
 		return s
 	}
 
-	res = reduceFunc(slices[0], slices[1])
+	res = reducer(slices[0], slices[1])
 
-	if len(slices) == 2 {
+	reduceSlice := make([][]T, 2, 2)
-		return Unique(res)
+	for i := 2; i < len(slices); i++ {
+		reduceSlice[0] = res
+		reduceSlice[1] = slices[i]
+		res = reducer(reduceSlice[0], reduceSlice[1])
 	}
 
-	tmp := make([][]T, 2, 2)
+	return Unique(res)
-	for i := 2; i < len(slices); i++ {
+}
-		tmp[0] = res
+
-		tmp[1] = slices[i]
+// SymmetricDifference oppoiste operation of intersection function
-		res = reduceFunc(tmp[0], tmp[1])
+func SymmetricDifference[T any](slices ...[]T) []T {
+	if len(slices) == 0 {
+		return []T{}
+	}
+	if len(slices) == 1 {
+		return Unique(slices[0])
+	}
+
+	res := make([]T, 0)
+
+	intersectSlice := Intersection(slices...)
+
+	for i := 0; i < len(slices); i++ {
+		slice := slices[i]
+		for _, v := range slice {
+			if !Contain(intersectSlice, v) {
+				res = append(res, v)
+			}
+		}
+
 	}
 
 	return Unique(res)

slice/slice_test.go

@@ -407,7 +407,18 @@ func TestIntersection(t *testing.T) {
 	for i := 0; i < len(res); i++ {
 		assert.Equal(expected[i], res[i])
 	}
-	// assert.IsNil(Intersection())
+}
+
+func TestSymmetricDifference(t *testing.T) {
+	assert := internal.NewAssert(t, "TestSymmetricDifference")
+
+	s1 := []int{1, 2, 3}
+	s2 := []int{1, 2, 4}
+	s3 := []int{1, 2, 3, 5}
+
+	assert.Equal([]int{1, 2, 3}, SymmetricDifference(s1))
+	assert.Equal([]int{3, 4}, SymmetricDifference(s1, s2))
+	assert.Equal([]int{3, 4, 5}, SymmetricDifference(s1, s2, s3))
 }
 
 func TestReverse(t *testing.T) {