It's often a requirement to defer a function: in order to complete a Future asynchronously, or to wait for the browser to paint.

Issues 3356 and 2705 can be resolved with an ability to defer a function.

window.setInterval(0, f) (and therefore new Timer(f, 0)) isn't sufficient because it does not invoke the callback on the current or next event loop, but waits at least 4ms (html5 spec) or longer depending on the browser.

IE 10 is adding setImmediate() to handler this and it can be emulated with postMessage.

GWT allows a command to be deferred either till the end of the current event loop, or to the beginning of the next, which follows layout/paint.

This function should live in the same library as Future so that Future can automatically defer Future.complete()