<pre>
const (
	c1 = imag(2i)                    // imag(2i) = 2.0 is a constant
	c2 = len([10]float64{2})         // [10]float64{2} contains no function calls
	c3 = len([10]float64{c1})        // [10]float64{c1} contains no function calls
	c4 = len([10]float64{imag(2i)})  // imag(2i) is a constant and no function call is issued
	c5 = len([10]float64{imag(z)})   // invalid: imag(z) is a (non-constant) function call
)
var z complex128

</p>

<p class="rule">
A send on a channel is synchronized before the completion of the
corresponding receive from that channel.
</p>

<p>
This program:
</p>

<pre>
var c = make(chan int, 10)
var a string

func f() {
	a = "hello, world"
	c &lt;- 0
}

func main() {
	go f()
	&lt;-c
	print(a)
}
</pre>

<p>

<a href="#" url="https://golang.org/change">commit</a>, or
<a href="#" url="https://golang.org/pkg/">pkg</a> id/name:</small>
<form style='margin: 0' id='navform'><nobr><input id="inputbox" size=10 tabindex=1 /><input type="submit" value="go" /></nobr></form>
<small>Also: <a href="#" url="https://build.golang.org">buildbots</a>
<a href="#" url="https://github.com/golang/go">GitHub</a>
</small>
</body>

<pre>
const (
	c1 = imag(2i)                    // imag(2i) = 2.0 is a constant
	c2 = len([10]float64{2})         // [10]float64{2} contains no function calls
	c3 = len([10]float64{c1})        // [10]float64{c1} contains no function calls
	c4 = len([10]float64{imag(2i)})  // imag(2i) is a constant and no function call is issued
	c5 = len([10]float64{imag(z)})   // invalid: imag(z) is a (non-constant) function call
)
var z complex128