test scanner writer interface bufio package

scanner_writer.go

package main

import (
	"bufio"
	"fmt"
	"os"
)

var scanner *bufio.Scanner = bufio.NewScanner(os.Stdin)
var writer *bufio.Writer = bufio.NewWriter(os.Stdout)

func main() {
	defer writer.Flush()
	scanner.Scan()
	str_slice := scanner.Text()
	writer.WriteString(str_slice + "\n")
	fmt.Print(str_slice)
}