40 lines
644 B
Go
40 lines
644 B
Go
// For more tutorials: https://blog.learngoprogramming.com
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//
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// Copyright © 2018 Inanc Gumus
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// Learn Go Programming Course
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// License: https://creativecommons.org/licenses/by-nc-sa/4.0/
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//
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package main
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import "fmt"
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type printer interface {
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print()
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}
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type list []printer
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func (l list) print() {
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if len(l) == 0 {
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fmt.Println("Sorry. Our store is closed. We're waiting for the delivery 🚚.")
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return
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}
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for _, it := range l {
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it.print()
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}
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}
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func (l list) discount(ratio float64) {
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type discounter interface {
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discount(float64)
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}
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for _, it := range l {
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if it, ok := it.(discounter); ok {
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it.discount(ratio)
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}
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}
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}
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