not just rapid prototyping. Often times, when i write unit tests and the like, i use closures. In the system i work in, asserting an exception requires spawni

not just rapid prototyping. Often times, when i write unit tests and the like, i use closures. In the system i work in, asserting an exception requires spawning a new thread and then watching it burn, which is most easily accomplished with a closure. But also writing one-off tasks to be run in a new thread (even in prod) can take closures.