r13 := new(rot13Reader)
	r13.r = r
	return r13
}

func (r13 *rot13Reader) Read(p []byte) (int, error) {
	n, err := r13.r.Read(p)
	for i := 0; i < n; i++ {
		c := p[i] | 0x20 // lowercase byte
		if 'a' <= c && c <= 'm' {
			p[i] += 13
		} else if 'n' <= c && c <= 'z' {
			p[i] -= 13
		}
	}
	return n, err
}

// Call ReadByte to accumulate the text of a file

operators, in increasing precedence:
</p>
<pre class="grammar">
|   alternation
()  grouping
[]  option (0 or 1 times)
{}  repetition (0 to n times)
</pre>

<p>
Lowercase production names are used to identify lexical (terminal) tokens.
Non-terminals are in CamelCase. Lexical tokens are enclosed in
double quotes <code>""</code> or back quotes <code>``</code>.
</p>

<p>

pkg time, method (*Timer) Reset(Duration) bool
pkg time, method (Time) Round(Duration) Time
pkg time, method (Time) Truncate(Duration) Time
pkg time, method (Time) YearDay() int
pkg unicode, const LowerCase = 1
pkg unicode, const MaxASCII = 127
pkg unicode, const MaxCase = 3
pkg unicode, const MaxLatin1 = 255
pkg unicode, const MaxRune = 1114111
pkg unicode, const ReplacementChar = 65533