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本文主要研究一下gost的HashSet
HashSet
gost/container/set/hashset.go
var itemExists = struct{}{}
type HashSet struct {
Items map[interface{}]struct{}
}
func NewSet(values ...interface{}) *HashSet {
set := &HashSet{Items: make(map[interface{}]struct{})}
if len(values) > 0 {
set.Add(values...)
}
return set
}
func (set *HashSet) Add(items ...interface{}) {
for _, item := range items {
set.Items[item] = itemExists
}
}
func (set *HashSet) Remove(items ...interface{}) {
for _, item := range items {
delete(set.Items, item)
}
}
func (set *HashSet) Contains(items ...interface{}) bool {
for _, item := range items {
if _, contains := set.Items[item]; !contains {
return false
}
}
return true
}
func (set *HashSet) Empty() bool {
return set.Size() == 0
}
func (set *HashSet) Size() int {
return len(set.Items)
}
func (set *HashSet) Clear() {
set.Items = make(map[interface{}]struct{})
}
func (set *HashSet) Values() []interface{} {
values := make([]interface{}, set.Size())
count := 0
for item := range set.Items {
values[count] = item
count++
}
return values
}
func (set *HashSet) String() string {
str := "HashSet\n"
var items []string
for k := range set.Items {
items = append(items, fmt.Sprintf("%v", k))
}
str += strings.Join(items, ", ")
return str
}
HashSet定义了Items属性；NewSet根据values来创建HashSet；它提供了Add、Remove、Contains、Empty、Size、Clear、Values、String方法
实例
gost/container/set/hashset_test.go
func TestSetNew(t *testing.T) {
set := NewSet(2, 1)
if actualValue := set.Size(); actualValue != 2 {
t.Errorf("Got %v expected %v", actualValue, 2)
}
if actualValue := set.Contains(1); actualValue != true {
t.Errorf("Got %v expected %v", actualValue, true)
}
if actualValue := set.Contains(2); actualValue != true {
t.Errorf("Got %v expected %v", actualValue, true)
}
if actualValue := set.Contains(3); actualValue != false {
t.Errorf("Got %v expected %v", actualValue, true)
}
}
小结
gost的HashSet定义了Items属性，它通过map结构来实现，它提供了Add、Remove、Contains、Empty、Size、Clear、Values、String方法。
