os.Stdout.Write(b)
	// Output: Hello, world!
}

func ExampleTrimRight() {
	fmt.Print(string(bytes.TrimRight([]byte("453gopher8257"), "0123456789")))
	// Output:
	// 453gopher
}

func ExampleTrimRightFunc() {
	fmt.Println(string(bytes.TrimRightFunc([]byte("go-gopher"), unicode.IsLetter)))
	fmt.Println(string(bytes.TrimRightFunc([]byte("go-gopher!"), unicode.IsPunct)))