npm install macrotask
setImmediateAPI, as specified, gives you access to the environment's task queue, sometimes known as its "macrotask" queue. This is crucially different from the microtask queue used by web features such as
MutationObserver, language features such as promises and
Object.observe, and Node.js features such as
process.nextTick. Each go-around of the macrotask queue yields back to the event loop once all queued tasks have been processed, even if the macrotask itself queued more macrotasks. Whereas, the microtask queue will continue executing any queued microtasks until it is exhausted.
In practice, what this means is that if you call
setImmediateinside of another task queued with
setImmediate, you will yield back to the event loop and any I/O or rendering tasks that need to take place between those calls, instead of executing the queued task as soon as possible.
The standard as it eventually got codified was that macrotasks were supposed to only get a single task from the queue per cycle instead of emptying the queue and cycling event loop before calling any recursive tasks.
This library ends up splitting the difference by tacking advantage of requestIdleCallback when available to run one or more tasks from the queue depending on how long they take, for environments that don't have requestIdleCallback we give ourselves a time limit of 10ms after which we will cycle the event loop before executing more tasks. At least one task will always be executed per loop.
npm install --save macrotask
provides 2 methods,
clear, they work just like setImmediate does where run enqueues a task
const task = macrotask;// prints hello there
and clear cancels it
const task = macrotask;macrotaskcleartask;// does not print anything
you can use it via a number of different methods:
// commonjs style in node or browserifyconst macrotask = ;// es6 style with rollup or babel;// or;
or you can just drop the
macrotask.min.js scripts from the root directory of the repo.