try {
      closingFuture.catching(
          Exception.class,
          new ClosingFunction<Exception, String>() {
            @Override
            public String apply(DeferredCloser closer1, Exception x1) throws Exception {
              return "value3";
            }
          },
          executor);
      fail();
    } catch (IllegalStateException expected3) {
    }
    try {

Thus the length and capacity of a slice literal are the maximum
element index plus one. A slice literal has the form
</p>

<pre>
[]T{x1, x2, … xn}
</pre>

<p>
and is shorthand for a slice operation applied to an array:
</p>

<pre>
tmp := [n]T{x1, x2, … xn}
tmp[0 : n]
</pre>

<p>
Within a composite literal of array, slice, or map type <code>T</code>,