<h3>Once</h3>
<p>
-The <code>once</code> package provides a safe mechanism for
-initialization in the presence of multiple goroutines.
+The <code>sync</code> package provides a safe mechanism for
+initialization in the presence of multiple goroutines
+through the use of the <code>Once</code> type.
Multiple threads can execute <code>once.Do(f)</code> for a particular <code>f</code>,
but only one will run <code>f()</code>, and the other calls block
until <code>f()</code> has returned.
<pre>
var a string
+var once sync.Once
func setup() {
a = "hello, world"