golangリングバッファReader Wirter Circle Buffer

package main

import (
	"errors"
	"fmt"
	"io"
	"time"
)

type CircleByteBuffer struct {
	io.Reader
	io.Writer
	io.Closer
	datas []byte

	start int
	end int
	size int
	isClose bool
	isEnd bool
}

func NewCircleByteBuffer(len int)*CircleByteBuffer{
	var e=new(CircleByteBuffer)
	e.datas=make([]byte,len)
	e.start=0
	e.end=0
	e.size=len
	e.isClose=false
	e.isEnd=false
	return e
}

func (e*CircleByteBuffer)getLen()int{
	if e.start==e.end{
		return 0
	}else if e.start=e.getLen() {
		panic("out buffer")
	}
	var pos=e.start+i
	if pos>=e.size {
		pos -= e.size
	}
	return e.datas[pos]
}

/*func (e*CircleByteBuffer)puts(bts []byte){
	for i:=0;i

func main() {
	fmt.Println("hello world")
	b:=NewCircleByteBuffer(1024)
	go func(){
		for i:=0;i<10;i++ {
			bts:=[]byte{byte(i)}
			b.Write(bts)
			time.Sleep(time.Second)
		}
		fmt.Println("Close!")
		b.Close()
	}()

	buf:=make([]byte,512)
	for{
		n,err:=b.Read(buf)
		if n>0{
			fmt.Println("Reads:",buf[0:n])
		}
		if err!=nil{
			break
		}
	}
	fmt.Println("end!")
}

hello world
Reads: [0]
Reads: [1]
Reads: [2]
Reads: [3]
Reads: [4]
Reads: [5]
Reads: [6]
Reads: [7]
Reads: [8]
Reads: [9]
Close!
end!