print(a)
}
</pre>

<p>
the assignment to <code>a</code> is not followed by
any synchronization event, so it is not guaranteed to be
observed by any other goroutine.
In fact, an aggressive compiler might delete the entire <code>go</code> statement.
</p>

<p>
If the effects of a goroutine must be observed by another goroutine,
use a synchronization mechanism such as a lock or channel

<p>
The built-in function <code>delete</code> removes the element with key
<code>k</code> from a <a href="#Map_types">map</a> <code>m</code>. The
type of <code>k</code> must be <a href="#Assignability">assignable</a>
to the key type of <code>m</code>.
</p>

<pre class="grammar">
delete(m, k)  // remove element m[k] from map m
</pre>

<p>

<p>
The built-in function <code>delete</code> removes the element with key
<code>k</code> from a <a href="#Map_types">map</a> <code>m</code>. The
value <code>k</code> must be <a href="#Assignability">assignable</a>
to the key type of <code>m</code>.
</p>

<pre class="grammar">
delete(m, k)  // remove element m[k] from map m
</pre>

<p>