41 lines
533 B
Go
41 lines
533 B
Go
// https://gobyexample.com/interfaces
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//
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package main
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import (
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"fmt"
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)
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type Geometry interface {
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Area() float64
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perim() float64
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}
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type rect struct {
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width, height float64
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}
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func (r rect) Area() float64 {
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return r.width * r.height
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}
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func (r rect) perim() float64 {
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return 2*r.width + 2*r.height
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}
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func (r rect) test_print() {
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fmt.Println(r.perim())
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}
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func measure(g Geometry) {
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fmt.Println(g)
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fmt.Println(g.Area())
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fmt.Println(g.perim())
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}
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func main() {
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r := rect{width: 3, height: 4}
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measure(r)
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r.test_print()
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}
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