update book code

eBook/examples/chapter_7/copy_append_slice.go

@@ -1,15 +1,16 @@
-package main
-import "fmt"
-
-func main() {
-    sl_from := []int{1, 2, 3}
-    sl_to := make([]int, 10)
-
-    n := copy(sl_to, sl_from)
-    fmt.Println(sl_to)
-    fmt.Printf("Copied %d elements\n", n) // n == 3
-
-    sl3 := []int{1, 2, 3}
-    sl3 = append(sl3, 4, 5, 6)
-    fmt.Println(sl3)
-}
+package main
+
+import "fmt"
+
+func main() {
+	sl_from := []int{1,2,3}
+	sl_to := make([]int,10)
+	
+	n := copy(sl_to, sl_from)
+	fmt.Println(sl_to)  // output: [1 2 3 0 0 0 0 0 0 0]
+	fmt.Printf("Copied %d elements\n", n)  // n == 3
+	
+	sl3 := []int{1,2,3}
+	sl3 = append(sl3, 4, 5, 6)
+	fmt.Println(sl3)  // output: [1 2 3 4 5 6]
+}