// Invalid runes, including negative ones, should be written as
	// utf8.RuneError.
	for _, r := range []rune{-1, utf8.MaxRune + 1} {
		var buf Buffer
		buf.WriteRune(r)
		check(t, fmt.Sprintf("TestWriteInvalidRune (%d)", r), &buf, "\uFFFD")
	}
}

func TestNext(t *testing.T) {
	b := []byte{0, 1, 2, 3, 4}
	tmp := make([]byte, 5)
	for i := 0; i <= 5; i++ {
		for j := i; j <= 5; j++ {

iteration's variable at that moment.
</p>

<pre>
var prints []func()
for i := 0; i < 5; i++ {
	prints = append(prints, func() { println(i) })
	i++
}
for _, p := range prints {
	p()
}
</pre>

<p>
prints
</p>

<pre>
1
3
5
</pre>

<p>