interfaces: refactor

interfaces/04-interfaces/game.go

@@ -0,0 +1,28 @@
+// For more tutorials: https://blog.learngoprogramming.com
+//
+// Copyright © 2018 Inanc Gumus
+// Learn Go Programming Course
+// License: https://creativecommons.org/licenses/by-nc-sa/4.0/
+//
+
+package main
+
+import "fmt"
+
+type game struct {
+	title string
+	price float64
+}
+
+func (g *game) print() {
+	fmt.Printf("%-15s: $%.2f\n", g.title, g.price)
+}
+
+func (g *game) discount(ratio float64) {
+	g.price *= (1 - ratio)
+}
+
+// TODO: NEW
+func (g *game) total() float64 {
+	return g.price
+}