之前想写一个文本编辑器，这是数据结构

gapbuffer.go

package main

import "fmt"

type gapBuffer struct {
	buff  []byte
	begin int
	size  int
}

//NewGapBuffer 创建一个空白的 gapbuffer
func NewGapBuffer() *gapBuffer {
	gapBuffer := gapBuffer{[]byte{0, 1, 2, 3, 4, 5, 6, 0, 0, 0}, 7, 3}
	//gapBuffer := gapBuffer{[]byte{'0', '1', '2', '3', '4', '5', '6', '7', '8', '9'}, 0, 3}
	fmt.Println(gapBuffer.buff)
	return &gapBuffer
}
func (g *gapBuffer) InsertAt(index int, b byte) {
	// fmt.Println(g.buff)

	if g.size == 0 {
		//容量不够了，要扩容
		//扩容多少呢，扩容3吧
		moreBuff := 3
		g.buff = append(g.buff, make([]byte, moreBuff)...)
		//扩容之后把最后的空格移动到gap这里来
		for i := 0; i < len(g.buff)-g.begin-moreBuff; i++ {
			g.buff[len(g.buff)-i-1] = g.buff[len(g.buff)-moreBuff-i-1]
		}
		g.size += moreBuff
	}

	if index < g.begin {
		//0123456789
		//abcdefg...
		//abcdef...g
		//abcde...fg
		for i := 0; i < g.begin-index; i++ {
			g.buff[g.begin+g.size-i-1] = g.buff[g.begin-i-1]
			// fmt.Println(g.buff)
		}
	} else if index > g.begin {
		//...abcdefg
		//a...bcdefg
		//ab...cdefg
		for i := 0; i < index-g.begin; i++ {
			// [gap---in]dex  由于buff中的gap不可见，不会存在index在末尾导致的buff溢出
			g.buff[g.begin+i] = g.buff[g.begin+g.size+i]
			// fmt.Println(g.buff)
		}
	}
	g.begin = index
	g.buff[g.begin] = b //插入数据
	g.begin++           //移动到gap下个位置
	g.size--            //容量减1
}
func (g *gapBuffer) DeleteAt(index int) {
	if g.size == 0 {
		g.begin = index
	}
	if index <= g.begin { //简单
		for i := 0; i < g.begin-index-1; i++ {
			g.buff[g.begin+g.size-i-1] = g.buff[g.begin-i-1]
			// fmt.Println(g.buff)
		}
	} else if index > g.begin {
		for i := 0; i < index-g.begin; i++ {
			g.buff[g.begin+i] = g.buff[g.begin+g.size+i]
			// fmt.Println(g.buff)
		}
	}
	g.size++
	g.begin = index
	// fmt.Println(g.buff, g.begin, g.size)
}
func (g *gapBuffer) Insert(index int, str string) {
	for i, c := range str {
		g.InsertAt(index+i, byte(c))
		// fmt.Println(g.buff)
	}
}
func (g *gapBuffer) Delete(index int, number int) {
	for i := 0; i < number; i++ {
		g.DeleteAt(index - i)
		fmt.Println(g.buff, g.begin, g.size)
	}
}

func (g *gapBuffer) ToString() string {
	return string(g.buff[:g.begin]) + string(g.buff[g.begin+g.size:])
}

func main() {
	NewGapBuffer().Delete(5, 2)
}