46 lines
702 B
Go
46 lines
702 B
Go
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package main
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import (
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"fmt"
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"io"
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"os"
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"time"
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)
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const finalWord = "Go!"
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const countdownStart = 3
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type Sleeper interface {
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Sleep()
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}
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type DefaultSleeper struct {
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}
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type ConfigurableSleeper struct {
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duration time.Duration
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sleep func(duration time.Duration)
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}
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func Countdown_main() {
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sleeper := &ConfigurableSleeper{1 * time.Second, time.Sleep}
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Countdown(os.Stdout, sleeper)
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}
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func (d *DefaultSleeper) Sleep() {
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time.Sleep(1 * time.Second)
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}
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func Countdown(out io.Writer, sleeper Sleeper) {
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for i := countdownStart; i > 0; i-- {
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sleeper.Sleep()
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fmt.Fprintln(out, i)
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}
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sleeper.Sleep()
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fmt.Fprint(out, finalWord)
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}
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func (c *ConfigurableSleeper) Sleep() {
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c.sleep(c.duration)
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}
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