slow pager first show stdin with fullspeed, then slow down

slow.go

// slow pager
// show fullspeed duaring full_speed_period, then show with wait_per_line sleep

package main

import (
	"bufio"
	"flag"
	"fmt"
	"os"
	"time"
)

// first fullspeed period
const full_speed_duaring = 1 * time.Second

func main() {
	wait := flag.Int("w", 500, "wait per line (millisecond)")
	flag.Parse()
	wait_per_line := time.Duration(*wait) * time.Millisecond

	start := time.Now()
	stdin := bufio.NewScanner(os.Stdin)
	for stdin.Scan() {
		text := stdin.Text()
		fmt.Println(text)
		if time.Since(start) > full_speed_duaring {
			time.Sleep(wait_per_line)
		}
	}
}