1package main
 2
 3import "testing"
 4import "fmt"
 5
 6func TestAdder(t *testing.T) {
 7	sum := Add(2, 2)
 8	expected := 4
 9
10	if sum != expected {
11		t.Errorf("expected '%d' but got '%d'", expected, sum)
12	}
13}
14
15func ExampleAdd() {
16	sum := Add(1, 5)
17	fmt.Println(sum)
18	// Output: 6
19}