func (c *Cursor) Back(n int) {
	fmt.Fprintf(c.Out, "\x1b[%dD", n)
}
Back moves the cursor n cells to left.
package terminal
import (
	"bufio"
	"bytes"
	"fmt"
	"io"
	"regexp"
	"strconv"
)
var COORDINATE_SYSTEM_BEGIN Short = 1
var dsrPattern = regexp.MustCompile(`\x1b\[(\d+);(\d+)R$`)
type Cursor struct {
	In  FileReader
	Out FileWriter
}
func (c *Cursor) Up(n int) {
	fmt.Fprintf(c.Out, "\x1b[%dA", n)
}
func (c *Cursor) Down(n int) {
	fmt.Fprintf(c.Out, "\x1b[%dB", n)
}
func (c *Cursor) Forward(n int) {
	fmt.Fprintf(c.Out, "\x1b[%dC", n)
}