chan<- float64  // can only be used to send float64s
<-chan int      // can only be used to receive ints
</pre>

<p>
The <code>&lt;-</code> operator associates with the leftmost <code>chan</code>
possible:
</p>

<pre>
chan&lt;- chan int    // same as chan&lt;- (chan int)
chan&lt;- &lt;-chan int  // same as chan&lt;- (&lt;-chan int)