fail to complete, as its continuation may
disappear - it will be as if the a-sync or compose-a-sync block
concerned had come to an end.  It may therefore be best only to call
this procedure on an event loop after all such await-* procedures
which are executing have returned.
</p>
<p>This procedure should not throw an exception unless memory is
exhausted.
</p>
<p>This procedure is first available in version 0.19 of this library.
</p></dd></dl>

<dl class="def">
<dt id="index-await_002dtask_002din_002dthread_