33 lines
662 B
Go
33 lines
662 B
Go
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// methods defined on struct types
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package main
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import "fmt"
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type rect struct {
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width, height int
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}
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// area method has a receiver type of *rect
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func (r *rect) area() int {
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return r.width * r.height
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}
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// Methods can be defined for either pointer or value receiver types
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func (r rect) perim() int {
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return 2*r.width + 2*r.height
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}
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func main() {
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r := rect{width: 10, height: 5}
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// call 2 methods defined for the struct
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fmt.Println("area: ", r.area())
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fmt.Println("perim:", r.perim())
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// Go automatically handles conversion between values and pointers for method calls
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rp := &r
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fmt.Println("area: ", rp.area())
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fmt.Println("perim:", rp.perim())
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}
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