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

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

<p>
The form <code>a … b</code> represents the set of characters from

In the rewritten program, the other goroutine can observe <code>2</code>, which was previously impossible.
</p>

<p>
Not introducing data races also means not assuming that loops terminate.
For example, a compiler must in general not move the accesses to <code>*p</code> or <code>*q</code>
ahead of the loop in this program:
</p>

<pre>
n := 0
for e := list; e != nil; e = e.next {
	n++
}

</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>
The form <code>a … b</code> represents the set of characters from