> it becomes easier to shoot yourself in the foot (which is mentioned in the alternative title, but doesn't seem to be expanded on much) -- say, by closing a Ha

> it becomes easier to shoot yourself in the foot (which is mentioned in the alternative title, but doesn't seem to be expanded on much) -- say, by closing a Handle lazy I/O (such as file reads) is suspect and even bad, but laziness + IO (or something like it) is a great way to stream from an API: http://blog.vmchale.com/article/lazy-io http://blog.vmchale.com/article/lazy-io Makes it possible to transcode for one. Basically makes streaming "compose" nicely - bzip2 and lzip otherwise have very different ways of streaming! And one would have to line a lot of things up.