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    immediate
    DefinitelyTyped icon, indicating that this package has TypeScript declarations provided by the separate @types/immediate package

    3.3.0 • Public • Published

    immediate Build Status

    testling status

    npm install immediate --save
    

    then

    var immediate = require("immediate");
     
    immediate(function () {
      // this will run soon
    });
     
    immediate(function (arg1, arg2) {
      // get your args like in iojs
    }, thing1, thing2);

    Introduction

    immediate is a microtask library, descended from NobleJS's setImmediate, but including ideas from Cujo's When and RSVP.

    immediate takes the tricks from setImmediate and RSVP and combines them with the scheduler inspired (vaguely) by when's.

    Note versions 2.6.5 and earlier were strictly speaking a 'macrotask' library not a microtask one, see this for the difference, if you need a macrotask library, I got you covered.

    Several new features were added in versions 3.1.0 and 3.2.0 to maintain parity with process.nextTick, but the 3.0.x series is still being kept up to date if you just need the small barebones version

    The Tricks

    process.nextTick

    Note that we check for actual Node.js environments, not emulated ones like those produced by browserify or similar.

    queueMicrotask

    Function available in major browser these days which you can use to add a function into the microtask queue managed by V8.

    MutationObserver

    This is what RSVP uses, it's very fast, details on MDN.

    MessageChannel

    Unfortunately, postMessage has completely different semantics inside web workers, and so cannot be used there. So we turn to MessageChannel, which has worse browser support, but does work inside a web worker.

    <script> onreadystatechange

    For our last trick, we pull something out to make things fast in Internet Explorer versions 6 through 8: namely, creating a <script> element and firing our calls in its onreadystatechange event. This does execute in a future turn of the event loop, and is also faster than setTimeout(…, 0), so hey, why not?

    Tricks we don't use

    setImmediate

    We avoid using setImmediate because node's process.nextTick is better suited to our needs. Additionally, Internet Explorer 10's implementation of setImmediate is broken.

    Reference and Reading

    Keywords

    none

    Install

    npm i immediate

    DownloadsWeekly Downloads

    4,776,533

    Version

    3.3.0

    License

    MIT

    Unpacked Size

    21 kB

    Total Files

    15

    Last publish

    Collaborators

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