initial commit

methods/methods.go

@@ -0,0 +1,34 @@
+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())
+}