// after successful read
	if _, err := b.ReadBytes('m'); err != nil {
		t.Fatalf("ReadBytes: %v", err)
	}
	if err := b.UnreadByte(); err != nil {
		t.Fatalf("UnreadByte: %v", err)
	}
	c, err := b.ReadByte()
	if err != nil {
		t.Fatalf("ReadByte: %v", err)
	}
	if c != 'm' {
		t.Errorf("ReadByte = %q; want %q", c, 'm')
	}
}

// Tests that we occasionally compact. Issue 5154.

with the same name as a result parameter is in
<a href="#Declarations_and_scope">scope</a> at the place of the return.
</p>

<pre>
func f(n int) (res int, err error) {
	if _, err := f(n-1); err != nil {
		return  // invalid return statement: err is shadowed
	}
	return
}
</pre>

<h3 id="Break_statements">Break statements</h3>

<p>
A "break" statement terminates execution of the innermost