Struct

2moretypes/struct.go

@@ -0,0 +1,56 @@
+package main
+
+import (
+	"fmt"
+)
+
+type Vertex struct {
+	X int
+	Y int
+}
+
+func main() {
+
+	fmt.Println("A struct is a collection of fields")
+	fmt.Println(Vertex{1, 2})
+
+	fmt.Println("struct fields are accessed by using a dot")
+	v := Vertex{6, 8}
+	fmt.Printf("%T, %v\n", v, v)
+	fmt.Printf("%T, %v\n", v.X, v.X)
+	fmt.Printf("%T, %v\n", v.Y, v.Y)
+
+	fmt.Printf("\n\n")
+
+	fmt.Println("Struct fields can be accessed through a struct pointer")
+	v2 := Vertex{6, 8}
+	p := &v2
+	// var p *Vertex = &v2 // ALSO VALID
+
+	(*p).X = 10
+	fmt.Printf("%T, %v, %p\n", p, p, p)
+	fmt.Printf("%T, %v\n", *p, *p)
+
+	fmt.Println("Go also allows to use struct pointers without * symbol while accesing elements:")
+	p.X = 15 // VALID
+	fmt.Println(*p)
+
+	fmt.Printf("\n\n")
+
+	fmt.Println("You can also use struct literals for assigning struct elements")
+	var (
+		v3 = Vertex{10, 20}
+		v4 = Vertex{X: 1} // Y:0
+		v5 = Vertex{}     // X:0, Y:0
+		v6 = Vertex{Y: 15, X: 75}
+		p2 = &Vertex{1, 2}
+	)
+
+	fmt.Printf("%T, %v\n", v3, v3)
+	fmt.Printf("%T, %v\n", v4, v4)
+	fmt.Printf("%T, %v\n", v5, v5)
+	fmt.Printf("%T, %v\n", v6, v6)
+	fmt.Printf("%T, %v\n", p2, p2)
+	fmt.Printf("%T, %v\n", *p2, *p2)
+
+}