83 lines
1.4 KiB
Go
83 lines
1.4 KiB
Go
|
package main
|
||
|
|
|
||
|
|
import (
|
||
|
|
"fmt"
|
||
|
|
)
|
||
|
|
|
||
|
|
//Iterator object should implement this interface
|
||
|
|
type Iterator interface {
|
||
|
|
First()
|
||
|
|
Next() bool
|
||
|
|
Done() bool
|
||
|
|
CurrentItem() interface{}
|
||
|
|
}
|
||
|
|
|
||
|
|
//A list object should implement Iterable interface in order to be a iterable list
|
||
|
|
type Iterable interface {
|
||
|
|
CreateIterator() Iterator
|
||
|
|
}
|
||
|
|
|
||
|
|
//Iterator object
|
||
|
|
type ListIterator struct {
|
||
|
|
data []string
|
||
|
|
index int
|
||
|
|
}
|
||
|
|
|
||
|
|
func (i *ListIterator) Done() bool {
|
||
|
|
return i.index >= len(i.data)
|
||
|
|
}
|
||
|
|
|
||
|
|
func (i *ListIterator) CurrentItem() interface{} {
|
||
|
|
return i.data[i.index]
|
||
|
|
}
|
||
|
|
|
||
|
|
func (i *ListIterator) First() {
|
||
|
|
i.index = 0
|
||
|
|
}
|
||
|
|
|
||
|
|
func (i *ListIterator) Next() bool {
|
||
|
|
i.index++
|
||
|
|
if i.Done() {
|
||
|
|
return false
|
||
|
|
}
|
||
|
|
return true
|
||
|
|
}
|
||
|
|
|
||
|
|
//Actual a basic list object.I don't use abstraction here.
|
||
|
|
type List struct {
|
||
|
|
data []string
|
||
|
|
}
|
||
|
|
|
||
|
|
func (l *List) Append(str string) {
|
||
|
|
l.data = append(l.data, str)
|
||
|
|
}
|
||
|
|
|
||
|
|
func (l *List) Count() int {
|
||
|
|
return len(l.data)
|
||
|
|
}
|
||
|
|
|
||
|
|
func (l *List) CreateIterator() Iterator {
|
||
|
|
listIterator := &ListIterator{data: l.data, index: -1}
|
||
|
|
return listIterator
|
||
|
|
}
|
||
|
|
|
||
|
|
//Basic testing....
|
||
|
|
|
||
|
|
func main() {
|
||
|
|
lst := &List{data: make([]string, 0)}
|
||
|
|
lst.Append("A")
|
||
|
|
lst.Append("B")
|
||
|
|
lst.Append("C")
|
||
|
|
lst.Append("D")
|
||
|
|
lst.Append("E")
|
||
|
|
|
||
|
|
//time to iterate...
|
||
|
|
lstIterator := lst.CreateIterator()
|
||
|
|
for lstIterator.Next() {
|
||
|
|
fmt.Println("-", lstIterator.CurrentItem())
|
||
|
|
}
|
||
|
|
|
||
|
|
lstIterator.First()
|
||
|
|
fmt.Println("First:", lstIterator.CurrentItem())
|
||
|
|
}
|