node_modules/immediate/README.md · rowtype-yoga/yoga-r3f

git.iko.soy/rowtype-yoga/yoga-r3f

rowtype-yoga/yoga-r3f/node_modules/immediate/README.md

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1# immediate [![Build Status](https://travis-ci.org/calvinmetcalf/immediate.svg?branch=master)](https://travis-ci.org/calvinmetcalf/immediate)

3```

4npm install immediate --save

5```

7then

9```js

10var immediate = require("immediate");

12immediate(function () {

13 // this will run soon

14});

16immediate(function (arg1, arg2) {

17 // get your args like in iojs

18}, thing1, thing2);

19```

21## Introduction

23**immediate** is a microtask library, decended from [NobleJS's setImmediate](https://github.com/NobleJS/setImmediate), but including ideas from [Cujo's When](https://github.com/cujojs/when) and [RSVP][RSVP].

25immediate takes the tricks from setImmedate and RSVP and combines them with the schedualer inspired (vaugly) by whens.

27Note versions 2.6.5 and earlier were strictly speaking a 'macrotask' library not a microtask one, [see this for the difference](https://github.com/YuzuJS/setImmediate#macrotasks-and-microtasks), if you need a macrotask library, [I got you covered](https://github.com/calvinmetcalf/macrotask).

29Several new features were added in versions 3.1.0 and 3.2.0 to maintain parity with

30process.nextTick, but the 3.0.x series is still being kept up to date if you just need

31the small barebones version.

34## The Tricks

36### `process.nextTick`

38Note that we check for *actual* Node.js environments, not emulated ones like those produced by browserify or similar.

40### `MutationObserver`

42This is what [RSVP][RSVP] uses, it's very fast, details on [MDN](https://developer.mozilla.org/en-US/docs/Web/API/MutationObserver).

45### `MessageChannel`

47Unfortunately, `postMessage` has completely different semantics inside web workers, and so cannot be used there. So we

48turn to [`MessageChannel`][MessageChannel], which has worse browser support, but does work inside a web worker.

50### `<script> onreadystatechange`

52For our last trick, we pull something out to make things fast in Internet Explorer versions 6 through 8: namely,

53creating a `<script>` element and firing our calls in its `onreadystatechange` event. This does execute in a future

54turn of the event loop, and is also faster than `setTimeout(…, 0)`, so hey, why not?

56## Tricks we don't use

58### `setImmediate`

59We avoid this process.nextTick in node is better suited to our needs and in Internet Explorer 10 there is a broken version of setImmediate we avoid using this.

62In Node.js, do

64```

65npm install immediate

66```

68then

70```js

71var immediate = require("immediate");

72```

75## Reference and Reading

77 * [Efficient Script Yielding W3C Editor's Draft][spec]

78 * [W3C mailing list post introducing the specification][list-post]

79 * [IE Test Drive demo][ie-demo]

80 * [Introductory blog post by Nicholas C. Zakas][ncz]

81 * I wrote a couple blog pots on this, [part 1][my-blog-1] and [part 2][my-blog-2]

83[RSVP]: https://github.com/tildeio/rsvp.js

84[spec]: https://dvcs.w3.org/hg/webperf/raw-file/tip/specs/setImmediate/Overview.html

85[list-post]: http://lists.w3.org/Archives/Public/public-web-perf/2011Jun/0100.html

86[ie-demo]: http://ie.microsoft.com/testdrive/Performance/setImmediateSorting/Default.html

87[ncz]: http://www.nczonline.net/blog/2011/09/19/script-yielding-with-setimmediate/

88[nextTick]: http://nodejs.org/docs/v0.8.16/api/process.html#process_process_nexttick_callback

89[postMessage]: http://www.whatwg.org/specs/web-apps/current-work/multipage/web-messaging.html#posting-messages

90[MessageChannel]: http://www.whatwg.org/specs/web-apps/current-work/multipage/web-messaging.html#channel-messaging

91[cross-browser-demo]: http://calvinmetcalf.github.io/setImmediate-shim-demo

92[my-blog-1]:http://calvinmetcalf.com/post/61672207151/setimmediate-etc

93[my-blog-2]:http://calvinmetcalf.com/post/61761231881/javascript-schedulers