package main

import "fmt"

type rect struct {
	width, height int
}

//this area method has a reciever type of *rect
func (r *rect) area() int {
	return r.width * r.height
}

// Methods can be defined for either pointer or value reciever types
// heres an example of a value receiver
func (r rect) perim() int {
	return 2*r.width + 2*r.height
}

func main() {
	r := rect{width:10,height:5}

	//here we call the two methods defined for our struct
	fmt.Println("area:",r.area())
	fmt.Println("perim:",r.perim())

	//Go automatically handles conversion between values and pointers for method calls.
	//you may want to use a pointer receiver type to avoid copying on method calls or to allow
	//the method to mutate the receiving struct

	rp := &r
	fmt.Println("area:",rp.area())
	fmt.Println("perim:",rp.perim())
}