constant and <code>s</code> is evaluated.
</p>

<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

	{V(float64(168)), V(float32(168))},
	{V(float64(169)), V(float64(169))},

	// truncation
	{V(float64(1.5)), V(int(1))},

	// complex
	{V(complex64(1i)), V(complex64(1i))},
	{V(complex64(2i)), V(complex128(2i))},
	{V(complex128(3i)), V(complex64(3i))},
	{V(complex128(4i)), V(complex128(4i))},

	// string
	{V(string("hello")), V(string("hello"))},
	{V(string("bytes1")), V([]byte("bytes1"))},