Franklyn Turbak. 
<b>First-Class Synchronization Barriers.</b>
In <i>Proceedings of the International Conference on 
Functional Programming (ICFP '96)</i>.<hr>Our purpose is to promote a second-class mechanism --- the
synchronization barrier --- to a first-class value.  We introduce the
<i>synchron</i>, a novel synchronization mechanism
that enables the coordination of a dynamically varying set of
concurrent threads that share access to a first-class synchronization
token.  We demonstrate how synchrons can be used to modularly manage
resources in cases where existing techniques are either inapplicable
or non-modular. In particular, <i>synchronized lazy aggregates</i>
enable the first space-efficient aggregate data decomposition of a wide range
of algorithms. We also introduce <i>firstuse{explicit-demand graph
reduction</i>, a new semantic framework that we have developed to
describe concurrency and explain the meaning of a synchron rendezvous.<hr>[<a href="icfp96.ps">PS</a>]  [<a href="icfp96.pdf">PDF</a>]