Version 2.0.7 of the GNU Guile language is out. It adds an implementation
of "curly infix
expressions," per-port reader options, a number of extension loading
improvements, and something known as "nested futures": "Futures may now be nested: a future can itself spawn and then `touch'
other futures. In addition, any thread that touches a future that has
not completed now processes other futures while waiting for the touched
future to completed."