Golang 实现 set 集合，变相实现 切片去重、排序 功能

利用 map 数据 不允许键重名 的特点

# set_int.go

package utils

import (
	"sort"
	"sync"
)

// 实现 set 集合，变相实现 切片去重
// by phpgo.cnblogs.com
type IntSet struct {
	m map[int]bool
	sync.RWMutex
}

func NewIntSet() *IntSet {
	return &IntSet{
		m: map[int]bool{},
	}
}

func (s *IntSet) Add(items ...int) {
	s.Lock()
	defer s.Unlock()
	if len(items) == 0 {
		return
	}
	for _, item := range items {
		s.m[item] = true
	}
}

func (s *IntSet) Remove(items ...int) {
	s.Lock()
	defer s.Unlock()
	if len(items) == 0 {
		return
	}
	for _, item := range items {
		delete(s.m, item)
	}
}

func (s *IntSet) Has(item int) bool {
	s.RLock()
	defer s.RUnlock()
	_, ok := s.m[item]
	return ok
}

func (s *IntSet) Len() int {
	return len(s.List())
}

func (s *IntSet) Clear() {
	s.Lock()
	defer s.Unlock()
	s.m = map[int]bool{}
}

func (s *IntSet) IsEmpty() bool {
	if s.Len() == 0 {
		return true
	}
	return false
}

func (s *IntSet) List() []int {
	s.RLock()
	defer s.RUnlock()
	list := []int{}
	for item := range s.m {
		list = append(list, item)
	}
	return list
}

func (s *IntSet) SortList() []int {
	s.RLock()
	defer s.RUnlock()
	list := []int{}
	for item := range s.m {
		list = append(list, item)
	}
	sort.Ints(list)
	return list
}

# set_string.go

package utils

import (
	"sort"
	"sync"
)

// 实现 set 集合，变相实现 切片去重
// by 52php.cnblogs.com
type StringSet struct {
	m map[string]bool
	sync.RWMutex
}

func NewStringSet() *StringSet {
	return &StringSet{
		m: map[string]bool{},
	}
}

func (s *StringSet) Add(items ...string) {
	s.Lock()
	defer s.Unlock()
	if len(items) == 0 {
		return
	}
	for _, item := range items {
		s.m[item] = true
	}
}

func (s *StringSet) Remove(items ...string) {
	s.Lock()
	defer s.Unlock()
	if len(items) == 0 {
		return
	}
	for _, item := range items {
		delete(s.m, item)
	}
}

func (s *StringSet) Has(item string) bool {
	s.RLock()
	defer s.RUnlock()
	_, ok := s.m[item]
	return ok
}

func (s *StringSet) Len() int {
	return len(s.List())
}

func (s *StringSet) Clear() {
	s.Lock()
	defer s.Unlock()
	s.m = map[string]bool{}
}

func (s *StringSet) IsEmpty() bool {
	if s.Len() == 0 {
		return true
	}
	return false
}

func (s *StringSet) List() []string {
	s.RLock()
	defer s.RUnlock()
	list := []string{}
	for item := range s.m {
		list = append(list, item)
	}
	return list
}

func (s *StringSet) SortList() []string {
	s.RLock()
	defer s.RUnlock()
	list := []string{}
	for item := range s.m {
		list = append(list, item)
	}
	sort.Strings(list)
	return list
}

# 应用示例：

package main

import (
	"utils"
	"fmt"
)

func main() {

	// int 集合
	s := utils.NewIntSet()

	// 添加数据
	s.Add(5, 2, 4, 3, 5, 6, 7)

	// 去重后的值
	fmt.Println(s.List())

	// 排序后的值
	fmt.Println(s.SortList())



	// string 集合
	s2 := utils.NewStringSet()

	// 添加数据
	s2.Add("wen", "jian", "bao", "study", "goalng", "bao", "jian")

	// 去重后的值
	fmt.Println(s2.List())

	// 排序后的值
	fmt.Println(s2.SortList())
}