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31 lines
515 B
Go
31 lines
515 B
Go
package main
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import "fmt"
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type Shaper interface {
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Area() float32
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// Perimeter() float32
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}
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type Square struct {
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side float32
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}
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func (sq *Square) Area() float32 {
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return sq.side * sq.side
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}
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func main() {
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sq1 := new(Square)
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sq1.side = 5
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// var areaIntf Shaper
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// areaIntf = sq1
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// shorter, without separate declaration:
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// areaIntf := Shaper(sq1)
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// or even:
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areaIntf := sq1
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fmt.Printf("The square has area: %f\n", areaIntf.Area())
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}
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// The square has area: 25.000000
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