1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
|
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width">
<meta name="nodejs.org:node-version" content="v22.14.0">
<title>Timers | Node.js v22.14.0 Documentation</title>
<link rel="stylesheet" href="https://fonts.googleapis.com/css?family=Lato:400,700,400italic&display=fallback">
<link rel="stylesheet" href="assets/style.css">
<link rel="stylesheet" href="assets/hljs.css">
<link rel="canonical" href="https://nodejs.org/api/timers.html">
<script async defer src="assets/api.js" type="text/javascript"></script>
<script>
const storedTheme = localStorage.getItem('theme');
// Follow operating system theme preference
if (storedTheme === null && window.matchMedia) {
const mq = window.matchMedia('(prefers-color-scheme: dark)');
if (mq.matches) {
document.documentElement.classList.add('dark-mode');
}
} else if (storedTheme === 'dark') {
document.documentElement.classList.add('dark-mode');
}
</script>
<style>@media(max-width:1120px){.with-78-chars>.js-flavor-toggle{float:none;margin:0 0 1em auto;}}@media(max-width:1088px){.with-74-chars>.js-flavor-toggle{float:none;margin:0 0 1em auto;}}@media(max-width:326px){.with-13-chars>.js-flavor-toggle{float:none;margin:0 0 1em auto;}}@media(max-width:342px){.with-15-chars>.js-flavor-toggle{float:none;margin:0 0 1em auto;}}@media(max-width:334px){.with-14-chars>.js-flavor-toggle{float:none;margin:0 0 1em auto;}}</style>
</head>
<body class="alt apidoc" id="api-section-timers">
<a href="#apicontent" class="skip-to-content">Skip to content</a>
<div id="content" class="clearfix">
<div role="navigation" id="column2" class="interior">
<div id="intro" class="interior">
<a href="/" title="Go back to the home page">
Node.js
</a>
</div>
<ul>
<li><a href="documentation.html" class="nav-documentation">About this documentation</a></li>
<li><a href="synopsis.html" class="nav-synopsis">Usage and example</a></li>
</ul>
<hr class="line">
<ul>
<li><a href="assert.html" class="nav-assert">Assertion testing</a></li>
<li><a href="async_context.html" class="nav-async_context">Asynchronous context tracking</a></li>
<li><a href="async_hooks.html" class="nav-async_hooks">Async hooks</a></li>
<li><a href="buffer.html" class="nav-buffer">Buffer</a></li>
<li><a href="addons.html" class="nav-addons">C++ addons</a></li>
<li><a href="n-api.html" class="nav-n-api">C/C++ addons with Node-API</a></li>
<li><a href="embedding.html" class="nav-embedding">C++ embedder API</a></li>
<li><a href="child_process.html" class="nav-child_process">Child processes</a></li>
<li><a href="cluster.html" class="nav-cluster">Cluster</a></li>
<li><a href="cli.html" class="nav-cli">Command-line options</a></li>
<li><a href="console.html" class="nav-console">Console</a></li>
<li><a href="corepack.html" class="nav-corepack">Corepack</a></li>
<li><a href="crypto.html" class="nav-crypto">Crypto</a></li>
<li><a href="debugger.html" class="nav-debugger">Debugger</a></li>
<li><a href="deprecations.html" class="nav-deprecations">Deprecated APIs</a></li>
<li><a href="diagnostics_channel.html" class="nav-diagnostics_channel">Diagnostics Channel</a></li>
<li><a href="dns.html" class="nav-dns">DNS</a></li>
<li><a href="domain.html" class="nav-domain">Domain</a></li>
<li><a href="errors.html" class="nav-errors">Errors</a></li>
<li><a href="events.html" class="nav-events">Events</a></li>
<li><a href="fs.html" class="nav-fs">File system</a></li>
<li><a href="globals.html" class="nav-globals">Globals</a></li>
<li><a href="http.html" class="nav-http">HTTP</a></li>
<li><a href="http2.html" class="nav-http2">HTTP/2</a></li>
<li><a href="https.html" class="nav-https">HTTPS</a></li>
<li><a href="inspector.html" class="nav-inspector">Inspector</a></li>
<li><a href="intl.html" class="nav-intl">Internationalization</a></li>
<li><a href="modules.html" class="nav-modules">Modules: CommonJS modules</a></li>
<li><a href="esm.html" class="nav-esm">Modules: ECMAScript modules</a></li>
<li><a href="module.html" class="nav-module">Modules: <code>node:module</code> API</a></li>
<li><a href="packages.html" class="nav-packages">Modules: Packages</a></li>
<li><a href="typescript.html" class="nav-typescript">Modules: TypeScript</a></li>
<li><a href="net.html" class="nav-net">Net</a></li>
<li><a href="os.html" class="nav-os">OS</a></li>
<li><a href="path.html" class="nav-path">Path</a></li>
<li><a href="perf_hooks.html" class="nav-perf_hooks">Performance hooks</a></li>
<li><a href="permissions.html" class="nav-permissions">Permissions</a></li>
<li><a href="process.html" class="nav-process">Process</a></li>
<li><a href="punycode.html" class="nav-punycode">Punycode</a></li>
<li><a href="querystring.html" class="nav-querystring">Query strings</a></li>
<li><a href="readline.html" class="nav-readline">Readline</a></li>
<li><a href="repl.html" class="nav-repl">REPL</a></li>
<li><a href="report.html" class="nav-report">Report</a></li>
<li><a href="single-executable-applications.html" class="nav-single-executable-applications">Single executable applications</a></li>
<li><a href="sqlite.html" class="nav-sqlite">SQLite</a></li>
<li><a href="stream.html" class="nav-stream">Stream</a></li>
<li><a href="string_decoder.html" class="nav-string_decoder">String decoder</a></li>
<li><a href="test.html" class="nav-test">Test runner</a></li>
<li><a href="timers.html" class="nav-timers active">Timers</a></li>
<li><a href="tls.html" class="nav-tls">TLS/SSL</a></li>
<li><a href="tracing.html" class="nav-tracing">Trace events</a></li>
<li><a href="tty.html" class="nav-tty">TTY</a></li>
<li><a href="dgram.html" class="nav-dgram">UDP/datagram</a></li>
<li><a href="url.html" class="nav-url">URL</a></li>
<li><a href="util.html" class="nav-util">Utilities</a></li>
<li><a href="v8.html" class="nav-v8">V8</a></li>
<li><a href="vm.html" class="nav-vm">VM</a></li>
<li><a href="wasi.html" class="nav-wasi">WASI</a></li>
<li><a href="webcrypto.html" class="nav-webcrypto">Web Crypto API</a></li>
<li><a href="webstreams.html" class="nav-webstreams">Web Streams API</a></li>
<li><a href="worker_threads.html" class="nav-worker_threads">Worker threads</a></li>
<li><a href="zlib.html" class="nav-zlib">Zlib</a></li>
</ul>
<hr class="line">
<ul>
<li><a href="https://github.com/nodejs/node" class="nav-https-github-com-nodejs-node">Code repository and issue tracker</a></li>
</ul>
</div>
<div id="column1" data-id="timers" class="interior">
<header class="header">
<div class="header-container">
<h1>Node.js v22.14.0 documentation</h1>
<button class="theme-toggle-btn" id="theme-toggle-btn" title="Toggle dark mode/light mode" aria-label="Toggle dark mode/light mode" hidden>
<svg xmlns="http://www.w3.org/2000/svg" class="icon dark-icon" height="24" width="24">
<path fill="none" d="M0 0h24v24H0z" />
<path d="M11.1 12.08c-2.33-4.51-.5-8.48.53-10.07C6.27 2.2 1.98 6.59 1.98 12c0 .14.02.28.02.42.62-.27 1.29-.42 2-.42 1.66 0 3.18.83 4.1 2.15A4.01 4.01 0 0111 18c0 1.52-.87 2.83-2.12 3.51.98.32 2.03.5 3.11.5 3.5 0 6.58-1.8 8.37-4.52-2.36.23-6.98-.97-9.26-5.41z"/>
<path d="M7 16h-.18C6.4 14.84 5.3 14 4 14c-1.66 0-3 1.34-3 3s1.34 3 3 3h3c1.1 0 2-.9 2-2s-.9-2-2-2z"/>
</svg>
<svg xmlns="http://www.w3.org/2000/svg" class="icon light-icon" height="24" width="24">
<path d="M0 0h24v24H0z" fill="none" />
<path d="M6.76 4.84l-1.8-1.79-1.41 1.41 1.79 1.79 1.42-1.41zM4 10.5H1v2h3v-2zm9-9.95h-2V3.5h2V.55zm7.45 3.91l-1.41-1.41-1.79 1.79 1.41 1.41 1.79-1.79zm-3.21 13.7l1.79 1.8 1.41-1.41-1.8-1.79-1.4 1.4zM20 10.5v2h3v-2h-3zm-8-5c-3.31 0-6 2.69-6 6s2.69 6 6 6 6-2.69 6-6-2.69-6-6-6zm-1 16.95h2V19.5h-2v2.95zm-7.45-3.91l1.41 1.41 1.79-1.8-1.41-1.41-1.79 1.8z"/>
</svg>
</button>
</div>
<div id="gtoc">
<ul>
<li class="pinned-header">Node.js v22.14.0</li>
<li class="picker-header">
<a href="#toc-picker" aria-controls="toc-picker">
<span class="picker-arrow"></span>
Table of contents
</a>
<div class="picker" tabindex="-1"><div class="toc"><ul id="toc-picker">
<li><span class="stability_2"><a href="#timers">Timers</a></span>
<ul>
<li><a href="#class-immediate">Class: <code>Immediate</code></a>
<ul>
<li><a href="#immediatehasref"><code>immediate.hasRef()</code></a></li>
<li><a href="#immediateref"><code>immediate.ref()</code></a></li>
<li><a href="#immediateunref"><code>immediate.unref()</code></a></li>
<li><span class="stability_1"><a href="#immediatesymboldispose"><code>immediate[Symbol.dispose]()</code></a></span></li>
</ul>
</li>
<li><a href="#class-timeout">Class: <code>Timeout</code></a>
<ul>
<li><span class="stability_3"><a href="#timeoutclose"><code>timeout.close()</code></a></span></li>
<li><a href="#timeouthasref"><code>timeout.hasRef()</code></a></li>
<li><a href="#timeoutref"><code>timeout.ref()</code></a></li>
<li><a href="#timeoutrefresh"><code>timeout.refresh()</code></a></li>
<li><a href="#timeoutunref"><code>timeout.unref()</code></a></li>
<li><a href="#timeoutsymboltoprimitive"><code>timeout[Symbol.toPrimitive]()</code></a></li>
<li><span class="stability_1"><a href="#timeoutsymboldispose"><code>timeout[Symbol.dispose]()</code></a></span></li>
</ul>
</li>
<li><a href="#scheduling-timers">Scheduling timers</a>
<ul>
<li><a href="#setimmediatecallback-args"><code>setImmediate(callback[, ...args])</code></a></li>
<li><a href="#setintervalcallback-delay-args"><code>setInterval(callback[, delay[, ...args]])</code></a></li>
<li><a href="#settimeoutcallback-delay-args"><code>setTimeout(callback[, delay[, ...args]])</code></a></li>
</ul>
</li>
<li><a href="#cancelling-timers">Cancelling timers</a>
<ul>
<li><a href="#clearimmediateimmediate"><code>clearImmediate(immediate)</code></a></li>
<li><a href="#clearintervaltimeout"><code>clearInterval(timeout)</code></a></li>
<li><a href="#cleartimeouttimeout"><code>clearTimeout(timeout)</code></a></li>
</ul>
</li>
<li><a href="#timers-promises-api">Timers Promises API</a>
<ul>
<li><a href="#timerspromisessettimeoutdelay-value-options"><code>timersPromises.setTimeout([delay[, value[, options]]])</code></a></li>
<li><a href="#timerspromisessetimmediatevalue-options"><code>timersPromises.setImmediate([value[, options]])</code></a></li>
<li><a href="#timerspromisessetintervaldelay-value-options"><code>timersPromises.setInterval([delay[, value[, options]]])</code></a></li>
<li><span class="stability_1"><a href="#timerspromisesschedulerwaitdelay-options"><code>timersPromises.scheduler.wait(delay[, options])</code></a></span></li>
<li><span class="stability_1"><a href="#timerspromisesscheduleryield"><code>timersPromises.scheduler.yield()</code></a></span></li>
</ul>
</li>
</ul>
</li>
</ul></div></div>
</li>
<li class="picker-header">
<a href="#gtoc-picker" aria-controls="gtoc-picker">
<span class="picker-arrow"></span>
Index
</a>
<div class="picker" tabindex="-1" id="gtoc-picker"><ul>
<li><a href="documentation.html" class="nav-documentation">About this documentation</a></li>
<li><a href="synopsis.html" class="nav-synopsis">Usage and example</a></li>
<li>
<a href="index.html">Index</a>
</li>
</ul>
<hr class="line">
<ul>
<li><a href="assert.html" class="nav-assert">Assertion testing</a></li>
<li><a href="async_context.html" class="nav-async_context">Asynchronous context tracking</a></li>
<li><a href="async_hooks.html" class="nav-async_hooks">Async hooks</a></li>
<li><a href="buffer.html" class="nav-buffer">Buffer</a></li>
<li><a href="addons.html" class="nav-addons">C++ addons</a></li>
<li><a href="n-api.html" class="nav-n-api">C/C++ addons with Node-API</a></li>
<li><a href="embedding.html" class="nav-embedding">C++ embedder API</a></li>
<li><a href="child_process.html" class="nav-child_process">Child processes</a></li>
<li><a href="cluster.html" class="nav-cluster">Cluster</a></li>
<li><a href="cli.html" class="nav-cli">Command-line options</a></li>
<li><a href="console.html" class="nav-console">Console</a></li>
<li><a href="corepack.html" class="nav-corepack">Corepack</a></li>
<li><a href="crypto.html" class="nav-crypto">Crypto</a></li>
<li><a href="debugger.html" class="nav-debugger">Debugger</a></li>
<li><a href="deprecations.html" class="nav-deprecations">Deprecated APIs</a></li>
<li><a href="diagnostics_channel.html" class="nav-diagnostics_channel">Diagnostics Channel</a></li>
<li><a href="dns.html" class="nav-dns">DNS</a></li>
<li><a href="domain.html" class="nav-domain">Domain</a></li>
<li><a href="errors.html" class="nav-errors">Errors</a></li>
<li><a href="events.html" class="nav-events">Events</a></li>
<li><a href="fs.html" class="nav-fs">File system</a></li>
<li><a href="globals.html" class="nav-globals">Globals</a></li>
<li><a href="http.html" class="nav-http">HTTP</a></li>
<li><a href="http2.html" class="nav-http2">HTTP/2</a></li>
<li><a href="https.html" class="nav-https">HTTPS</a></li>
<li><a href="inspector.html" class="nav-inspector">Inspector</a></li>
<li><a href="intl.html" class="nav-intl">Internationalization</a></li>
<li><a href="modules.html" class="nav-modules">Modules: CommonJS modules</a></li>
<li><a href="esm.html" class="nav-esm">Modules: ECMAScript modules</a></li>
<li><a href="module.html" class="nav-module">Modules: <code>node:module</code> API</a></li>
<li><a href="packages.html" class="nav-packages">Modules: Packages</a></li>
<li><a href="typescript.html" class="nav-typescript">Modules: TypeScript</a></li>
<li><a href="net.html" class="nav-net">Net</a></li>
<li><a href="os.html" class="nav-os">OS</a></li>
<li><a href="path.html" class="nav-path">Path</a></li>
<li><a href="perf_hooks.html" class="nav-perf_hooks">Performance hooks</a></li>
<li><a href="permissions.html" class="nav-permissions">Permissions</a></li>
<li><a href="process.html" class="nav-process">Process</a></li>
<li><a href="punycode.html" class="nav-punycode">Punycode</a></li>
<li><a href="querystring.html" class="nav-querystring">Query strings</a></li>
<li><a href="readline.html" class="nav-readline">Readline</a></li>
<li><a href="repl.html" class="nav-repl">REPL</a></li>
<li><a href="report.html" class="nav-report">Report</a></li>
<li><a href="single-executable-applications.html" class="nav-single-executable-applications">Single executable applications</a></li>
<li><a href="sqlite.html" class="nav-sqlite">SQLite</a></li>
<li><a href="stream.html" class="nav-stream">Stream</a></li>
<li><a href="string_decoder.html" class="nav-string_decoder">String decoder</a></li>
<li><a href="test.html" class="nav-test">Test runner</a></li>
<li><a href="timers.html" class="nav-timers active">Timers</a></li>
<li><a href="tls.html" class="nav-tls">TLS/SSL</a></li>
<li><a href="tracing.html" class="nav-tracing">Trace events</a></li>
<li><a href="tty.html" class="nav-tty">TTY</a></li>
<li><a href="dgram.html" class="nav-dgram">UDP/datagram</a></li>
<li><a href="url.html" class="nav-url">URL</a></li>
<li><a href="util.html" class="nav-util">Utilities</a></li>
<li><a href="v8.html" class="nav-v8">V8</a></li>
<li><a href="vm.html" class="nav-vm">VM</a></li>
<li><a href="wasi.html" class="nav-wasi">WASI</a></li>
<li><a href="webcrypto.html" class="nav-webcrypto">Web Crypto API</a></li>
<li><a href="webstreams.html" class="nav-webstreams">Web Streams API</a></li>
<li><a href="worker_threads.html" class="nav-worker_threads">Worker threads</a></li>
<li><a href="zlib.html" class="nav-zlib">Zlib</a></li>
</ul>
<hr class="line">
<ul>
<li><a href="https://github.com/nodejs/node" class="nav-https-github-com-nodejs-node">Code repository and issue tracker</a></li>
</ul></div>
</li>
<li class="picker-header">
<a href="#alt-docs" aria-controls="alt-docs">
<span class="picker-arrow"></span>
Other versions
</a>
<div class="picker" tabindex="-1"><ol id="alt-docs"><li><a href="https://nodejs.org/docs/latest-v23.x/api/timers.html">23.x</a></li>
<li><a href="https://nodejs.org/docs/latest-v22.x/api/timers.html">22.x <b>LTS</b></a></li>
<li><a href="https://nodejs.org/docs/latest-v21.x/api/timers.html">21.x</a></li>
<li><a href="https://nodejs.org/docs/latest-v20.x/api/timers.html">20.x <b>LTS</b></a></li>
<li><a href="https://nodejs.org/docs/latest-v19.x/api/timers.html">19.x</a></li>
<li><a href="https://nodejs.org/docs/latest-v18.x/api/timers.html">18.x <b>LTS</b></a></li>
<li><a href="https://nodejs.org/docs/latest-v17.x/api/timers.html">17.x</a></li>
<li><a href="https://nodejs.org/docs/latest-v16.x/api/timers.html">16.x</a></li>
<li><a href="https://nodejs.org/docs/latest-v15.x/api/timers.html">15.x</a></li>
<li><a href="https://nodejs.org/docs/latest-v14.x/api/timers.html">14.x</a></li>
<li><a href="https://nodejs.org/docs/latest-v13.x/api/timers.html">13.x</a></li>
<li><a href="https://nodejs.org/docs/latest-v12.x/api/timers.html">12.x</a></li>
<li><a href="https://nodejs.org/docs/latest-v11.x/api/timers.html">11.x</a></li>
<li><a href="https://nodejs.org/docs/latest-v10.x/api/timers.html">10.x</a></li>
<li><a href="https://nodejs.org/docs/latest-v9.x/api/timers.html">9.x</a></li>
<li><a href="https://nodejs.org/docs/latest-v8.x/api/timers.html">8.x</a></li>
<li><a href="https://nodejs.org/docs/latest-v7.x/api/timers.html">7.x</a></li>
<li><a href="https://nodejs.org/docs/latest-v6.x/api/timers.html">6.x</a></li>
<li><a href="https://nodejs.org/docs/latest-v5.x/api/timers.html">5.x</a></li>
<li><a href="https://nodejs.org/docs/latest-v4.x/api/timers.html">4.x</a></li>
<li><a href="https://nodejs.org/docs/latest-v0.12.x/api/timers.html">0.12.x</a></li>
<li><a href="https://nodejs.org/docs/latest-v0.10.x/api/timers.html">0.10.x</a></li></ol></div>
</li>
<li class="picker-header">
<a href="#options-picker" aria-controls="options-picker">
<span class="picker-arrow"></span>
Options
</a>
<div class="picker" tabindex="-1">
<ul id="options-picker">
<li>
<a href="all.html">View on single page</a>
</li>
<li>
<a href="timers.json">View as JSON</a>
</li>
<li class="edit_on_github"><a href="https://github.com/nodejs/node/edit/main/doc/api/timers.md">Edit on GitHub</a></li>
</ul>
</div>
</li>
</ul>
</div>
<hr>
</header>
<details role="navigation" id="toc" open><summary>Table of contents</summary><ul>
<li><span class="stability_2"><a href="#timers">Timers</a></span>
<ul>
<li><a href="#class-immediate">Class: <code>Immediate</code></a>
<ul>
<li><a href="#immediatehasref"><code>immediate.hasRef()</code></a></li>
<li><a href="#immediateref"><code>immediate.ref()</code></a></li>
<li><a href="#immediateunref"><code>immediate.unref()</code></a></li>
<li><span class="stability_1"><a href="#immediatesymboldispose"><code>immediate[Symbol.dispose]()</code></a></span></li>
</ul>
</li>
<li><a href="#class-timeout">Class: <code>Timeout</code></a>
<ul>
<li><span class="stability_3"><a href="#timeoutclose"><code>timeout.close()</code></a></span></li>
<li><a href="#timeouthasref"><code>timeout.hasRef()</code></a></li>
<li><a href="#timeoutref"><code>timeout.ref()</code></a></li>
<li><a href="#timeoutrefresh"><code>timeout.refresh()</code></a></li>
<li><a href="#timeoutunref"><code>timeout.unref()</code></a></li>
<li><a href="#timeoutsymboltoprimitive"><code>timeout[Symbol.toPrimitive]()</code></a></li>
<li><span class="stability_1"><a href="#timeoutsymboldispose"><code>timeout[Symbol.dispose]()</code></a></span></li>
</ul>
</li>
<li><a href="#scheduling-timers">Scheduling timers</a>
<ul>
<li><a href="#setimmediatecallback-args"><code>setImmediate(callback[, ...args])</code></a></li>
<li><a href="#setintervalcallback-delay-args"><code>setInterval(callback[, delay[, ...args]])</code></a></li>
<li><a href="#settimeoutcallback-delay-args"><code>setTimeout(callback[, delay[, ...args]])</code></a></li>
</ul>
</li>
<li><a href="#cancelling-timers">Cancelling timers</a>
<ul>
<li><a href="#clearimmediateimmediate"><code>clearImmediate(immediate)</code></a></li>
<li><a href="#clearintervaltimeout"><code>clearInterval(timeout)</code></a></li>
<li><a href="#cleartimeouttimeout"><code>clearTimeout(timeout)</code></a></li>
</ul>
</li>
<li><a href="#timers-promises-api">Timers Promises API</a>
<ul>
<li><a href="#timerspromisessettimeoutdelay-value-options"><code>timersPromises.setTimeout([delay[, value[, options]]])</code></a></li>
<li><a href="#timerspromisessetimmediatevalue-options"><code>timersPromises.setImmediate([value[, options]])</code></a></li>
<li><a href="#timerspromisessetintervaldelay-value-options"><code>timersPromises.setInterval([delay[, value[, options]]])</code></a></li>
<li><span class="stability_1"><a href="#timerspromisesschedulerwaitdelay-options"><code>timersPromises.scheduler.wait(delay[, options])</code></a></span></li>
<li><span class="stability_1"><a href="#timerspromisesscheduleryield"><code>timersPromises.scheduler.yield()</code></a></span></li>
</ul>
</li>
</ul>
</li>
</ul></details>
<div role="main" id="apicontent">
<h2>Timers<span><a class="mark" href="#timers" id="timers">#</a></span><a aria-hidden="true" class="legacy" id="timers_timers"></a></h2>
<p></p><div class="api_stability api_stability_2"><a href="documentation.html#stability-index">Stability: 2</a> - Stable</div><p></p>
<p><strong>Source Code:</strong> <a href="https://github.com/nodejs/node/blob/v22.14.0/lib/timers.js">lib/timers.js</a></p>
<p>The <code>timer</code> module exposes a global API for scheduling functions to
be called at some future period of time. Because the timer functions are
globals, there is no need to call <code>require('node:timers')</code> to use the API.</p>
<p>The timer functions within Node.js implement a similar API as the timers API
provided by Web Browsers but use a different internal implementation that is
built around the Node.js <a href="https://nodejs.org/en/docs/guides/event-loop-timers-and-nexttick/#setimmediate-vs-settimeout">Event Loop</a>.</p>
<section><h3>Class: <code>Immediate</code><span><a class="mark" href="#class-immediate" id="class-immediate">#</a></span><a aria-hidden="true" class="legacy" id="timers_class_immediate"></a></h3>
<p>This object is created internally and is returned from <a href="#setimmediatecallback-args"><code>setImmediate()</code></a>. It
can be passed to <a href="#clearimmediateimmediate"><code>clearImmediate()</code></a> in order to cancel the scheduled
actions.</p>
<p>By default, when an immediate is scheduled, the Node.js event loop will continue
running as long as the immediate is active. The <code>Immediate</code> object returned by
<a href="#setimmediatecallback-args"><code>setImmediate()</code></a> exports both <code>immediate.ref()</code> and <code>immediate.unref()</code>
functions that can be used to control this default behavior.</p>
<h4><code>immediate.hasRef()</code><span><a class="mark" href="#immediatehasref" id="immediatehasref">#</a></span><a aria-hidden="true" class="legacy" id="timers_immediate_hasref"></a></h4>
<div class="api_metadata">
<span>Added in: v11.0.0</span>
</div>
<ul>
<li>Returns: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Boolean_type" class="type"><boolean></a></li>
</ul>
<p>If true, the <code>Immediate</code> object will keep the Node.js event loop active.</p>
<h4><code>immediate.ref()</code><span><a class="mark" href="#immediateref" id="immediateref">#</a></span><a aria-hidden="true" class="legacy" id="timers_immediate_ref"></a></h4>
<div class="api_metadata">
<span>Added in: v9.7.0</span>
</div>
<ul>
<li>Returns: <a href="timers.html#class-immediate" class="type"><Immediate></a> a reference to <code>immediate</code></li>
</ul>
<p>When called, requests that the Node.js event loop <em>not</em> exit so long as the
<code>Immediate</code> is active. Calling <code>immediate.ref()</code> multiple times will have no
effect.</p>
<p>By default, all <code>Immediate</code> objects are "ref'ed", making it normally unnecessary
to call <code>immediate.ref()</code> unless <code>immediate.unref()</code> had been called previously.</p>
<h4><code>immediate.unref()</code><span><a class="mark" href="#immediateunref" id="immediateunref">#</a></span><a aria-hidden="true" class="legacy" id="timers_immediate_unref"></a></h4>
<div class="api_metadata">
<span>Added in: v9.7.0</span>
</div>
<ul>
<li>Returns: <a href="timers.html#class-immediate" class="type"><Immediate></a> a reference to <code>immediate</code></li>
</ul>
<p>When called, the active <code>Immediate</code> object will not require the Node.js event
loop to remain active. If there is no other activity keeping the event loop
running, the process may exit before the <code>Immediate</code> object's callback is
invoked. Calling <code>immediate.unref()</code> multiple times will have no effect.</p>
<h4><code>immediate[Symbol.dispose]()</code><span><a class="mark" href="#immediatesymboldispose" id="immediatesymboldispose">#</a></span><a aria-hidden="true" class="legacy" id="timers_immediate_symbol_dispose"></a></h4>
<div class="api_metadata">
<span>Added in: v20.5.0, v18.18.0</span>
</div>
<p></p><div class="api_stability api_stability_1"><a href="documentation.html#stability-index">Stability: 1</a> - Experimental</div><p></p>
<p>Cancels the immediate. This is similar to calling <code>clearImmediate()</code>.</p>
</section><section><h3>Class: <code>Timeout</code><span><a class="mark" href="#class-timeout" id="class-timeout">#</a></span><a aria-hidden="true" class="legacy" id="timers_class_timeout"></a></h3>
<p>This object is created internally and is returned from <a href="#settimeoutcallback-delay-args"><code>setTimeout()</code></a> and
<a href="#setintervalcallback-delay-args"><code>setInterval()</code></a>. It can be passed to either <a href="#cleartimeouttimeout"><code>clearTimeout()</code></a> or
<a href="#clearintervaltimeout"><code>clearInterval()</code></a> in order to cancel the scheduled actions.</p>
<p>By default, when a timer is scheduled using either <a href="#settimeoutcallback-delay-args"><code>setTimeout()</code></a> or
<a href="#setintervalcallback-delay-args"><code>setInterval()</code></a>, the Node.js event loop will continue running as long as the
timer is active. Each of the <code>Timeout</code> objects returned by these functions
export both <code>timeout.ref()</code> and <code>timeout.unref()</code> functions that can be used to
control this default behavior.</p>
<h4><code>timeout.close()</code><span><a class="mark" href="#timeoutclose" id="timeoutclose">#</a></span><a aria-hidden="true" class="legacy" id="timers_timeout_close"></a></h4>
<div class="api_metadata">
<span>Added in: v0.9.1</span>
</div>
<p></p><div class="api_stability api_stability_3"><a href="documentation.html#stability-index">Stability: 3</a> - Legacy: Use <a href="#cleartimeouttimeout"><code>clearTimeout()</code></a> instead.</div><p></p>
<ul>
<li>Returns: <a href="timers.html#class-timeout" class="type"><Timeout></a> a reference to <code>timeout</code></li>
</ul>
<p>Cancels the timeout.</p>
<h4><code>timeout.hasRef()</code><span><a class="mark" href="#timeouthasref" id="timeouthasref">#</a></span><a aria-hidden="true" class="legacy" id="timers_timeout_hasref"></a></h4>
<div class="api_metadata">
<span>Added in: v11.0.0</span>
</div>
<ul>
<li>Returns: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Boolean_type" class="type"><boolean></a></li>
</ul>
<p>If true, the <code>Timeout</code> object will keep the Node.js event loop active.</p>
<h4><code>timeout.ref()</code><span><a class="mark" href="#timeoutref" id="timeoutref">#</a></span><a aria-hidden="true" class="legacy" id="timers_timeout_ref"></a></h4>
<div class="api_metadata">
<span>Added in: v0.9.1</span>
</div>
<ul>
<li>Returns: <a href="timers.html#class-timeout" class="type"><Timeout></a> a reference to <code>timeout</code></li>
</ul>
<p>When called, requests that the Node.js event loop <em>not</em> exit so long as the
<code>Timeout</code> is active. Calling <code>timeout.ref()</code> multiple times will have no effect.</p>
<p>By default, all <code>Timeout</code> objects are "ref'ed", making it normally unnecessary
to call <code>timeout.ref()</code> unless <code>timeout.unref()</code> had been called previously.</p>
<h4><code>timeout.refresh()</code><span><a class="mark" href="#timeoutrefresh" id="timeoutrefresh">#</a></span><a aria-hidden="true" class="legacy" id="timers_timeout_refresh"></a></h4>
<div class="api_metadata">
<span>Added in: v10.2.0</span>
</div>
<ul>
<li>Returns: <a href="timers.html#class-timeout" class="type"><Timeout></a> a reference to <code>timeout</code></li>
</ul>
<p>Sets the timer's start time to the current time, and reschedules the timer to
call its callback at the previously specified duration adjusted to the current
time. This is useful for refreshing a timer without allocating a new
JavaScript object.</p>
<p>Using this on a timer that has already called its callback will reactivate the
timer.</p>
<h4><code>timeout.unref()</code><span><a class="mark" href="#timeoutunref" id="timeoutunref">#</a></span><a aria-hidden="true" class="legacy" id="timers_timeout_unref"></a></h4>
<div class="api_metadata">
<span>Added in: v0.9.1</span>
</div>
<ul>
<li>Returns: <a href="timers.html#class-timeout" class="type"><Timeout></a> a reference to <code>timeout</code></li>
</ul>
<p>When called, the active <code>Timeout</code> object will not require the Node.js event loop
to remain active. If there is no other activity keeping the event loop running,
the process may exit before the <code>Timeout</code> object's callback is invoked. Calling
<code>timeout.unref()</code> multiple times will have no effect.</p>
<h4><code>timeout[Symbol.toPrimitive]()</code><span><a class="mark" href="#timeoutsymboltoprimitive" id="timeoutsymboltoprimitive">#</a></span><a aria-hidden="true" class="legacy" id="timers_timeout_symbol_toprimitive"></a></h4>
<div class="api_metadata">
<span>Added in: v14.9.0, v12.19.0</span>
</div>
<ul>
<li>Returns: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><integer></a> a number that can be used to reference this <code>timeout</code></li>
</ul>
<p>Coerce a <code>Timeout</code> to a primitive. The primitive can be used to
clear the <code>Timeout</code>. The primitive can only be used in the
same thread where the timeout was created. Therefore, to use it
across <a href="worker_threads.html"><code>worker_threads</code></a> it must first be passed to the correct
thread. This allows enhanced compatibility with browser
<code>setTimeout()</code> and <code>setInterval()</code> implementations.</p>
<h4><code>timeout[Symbol.dispose]()</code><span><a class="mark" href="#timeoutsymboldispose" id="timeoutsymboldispose">#</a></span><a aria-hidden="true" class="legacy" id="timers_timeout_symbol_dispose"></a></h4>
<div class="api_metadata">
<span>Added in: v20.5.0, v18.18.0</span>
</div>
<p></p><div class="api_stability api_stability_1"><a href="documentation.html#stability-index">Stability: 1</a> - Experimental</div><p></p>
<p>Cancels the timeout.</p>
</section><section><h3>Scheduling timers<span><a class="mark" href="#scheduling-timers" id="scheduling-timers">#</a></span><a aria-hidden="true" class="legacy" id="timers_scheduling_timers"></a></h3>
<p>A timer in Node.js is an internal construct that calls a given function after
a certain period of time. When a timer's function is called varies depending on
which method was used to create the timer and what other work the Node.js
event loop is doing.</p>
<h4><code>setImmediate(callback[, ...args])</code><span><a class="mark" href="#setimmediatecallback-args" id="setimmediatecallback-args">#</a></span><a aria-hidden="true" class="legacy" id="timers_setimmediate_callback_args"></a></h4>
<div class="api_metadata">
<details class="changelog"><summary>History</summary>
<table>
<tbody><tr><th>Version</th><th>Changes</th></tr>
<tr><td>v18.0.0</td>
<td><p>Passing an invalid callback to the <code>callback</code> argument now throws <code>ERR_INVALID_ARG_TYPE</code> instead of <code>ERR_INVALID_CALLBACK</code>.</p></td></tr>
<tr><td>v0.9.1</td>
<td><p><span>Added in: v0.9.1</span></p></td></tr>
</tbody></table>
</details>
</div>
<ul>
<li><code>callback</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function" class="type"><Function></a> The function to call at the end of this turn of
the Node.js <a href="https://nodejs.org/en/docs/guides/event-loop-timers-and-nexttick/#setimmediate-vs-settimeout">Event Loop</a></li>
<li><code>...args</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Data_types" class="type"><any></a> Optional arguments to pass when the <code>callback</code> is called.</li>
<li>Returns: <a href="timers.html#class-immediate" class="type"><Immediate></a> for use with <a href="#clearimmediateimmediate"><code>clearImmediate()</code></a></li>
</ul>
<p>Schedules the "immediate" execution of the <code>callback</code> after I/O events'
callbacks.</p>
<p>When multiple calls to <code>setImmediate()</code> are made, the <code>callback</code> functions are
queued for execution in the order in which they are created. The entire callback
queue is processed every event loop iteration. If an immediate timer is queued
from inside an executing callback, that timer will not be triggered until the
next event loop iteration.</p>
<p>If <code>callback</code> is not a function, a <a href="errors.html#class-typeerror"><code>TypeError</code></a> will be thrown.</p>
<p>This method has a custom variant for promises that is available using
<a href="#timerspromisessetimmediatevalue-options"><code>timersPromises.setImmediate()</code></a>.</p>
<h4><code>setInterval(callback[, delay[, ...args]])</code><span><a class="mark" href="#setintervalcallback-delay-args" id="setintervalcallback-delay-args">#</a></span><a aria-hidden="true" class="legacy" id="timers_setinterval_callback_delay_args"></a></h4>
<div class="api_metadata">
<details class="changelog"><summary>History</summary>
<table>
<tbody><tr><th>Version</th><th>Changes</th></tr>
<tr><td>v18.0.0</td>
<td><p>Passing an invalid callback to the <code>callback</code> argument now throws <code>ERR_INVALID_ARG_TYPE</code> instead of <code>ERR_INVALID_CALLBACK</code>.</p></td></tr>
<tr><td>v0.0.1</td>
<td><p><span>Added in: v0.0.1</span></p></td></tr>
</tbody></table>
</details>
</div>
<ul>
<li><code>callback</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function" class="type"><Function></a> The function to call when the timer elapses.</li>
<li><code>delay</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a> The number of milliseconds to wait before calling the
<code>callback</code>. <strong>Default:</strong> <code>1</code>.</li>
<li><code>...args</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Data_types" class="type"><any></a> Optional arguments to pass when the <code>callback</code> is called.</li>
<li>Returns: <a href="timers.html#class-timeout" class="type"><Timeout></a> for use with <a href="#clearintervaltimeout"><code>clearInterval()</code></a></li>
</ul>
<p>Schedules repeated execution of <code>callback</code> every <code>delay</code> milliseconds.</p>
<p>When <code>delay</code> is larger than <code>2147483647</code> or less than <code>1</code>, the <code>delay</code> will be
set to <code>1</code>. Non-integer delays are truncated to an integer.</p>
<p>If <code>callback</code> is not a function, a <a href="errors.html#class-typeerror"><code>TypeError</code></a> will be thrown.</p>
<p>This method has a custom variant for promises that is available using
<a href="#timerspromisessetintervaldelay-value-options"><code>timersPromises.setInterval()</code></a>.</p>
<h4><code>setTimeout(callback[, delay[, ...args]])</code><span><a class="mark" href="#settimeoutcallback-delay-args" id="settimeoutcallback-delay-args">#</a></span><a aria-hidden="true" class="legacy" id="timers_settimeout_callback_delay_args"></a></h4>
<div class="api_metadata">
<details class="changelog"><summary>History</summary>
<table>
<tbody><tr><th>Version</th><th>Changes</th></tr>
<tr><td>v18.0.0</td>
<td><p>Passing an invalid callback to the <code>callback</code> argument now throws <code>ERR_INVALID_ARG_TYPE</code> instead of <code>ERR_INVALID_CALLBACK</code>.</p></td></tr>
<tr><td>v0.0.1</td>
<td><p><span>Added in: v0.0.1</span></p></td></tr>
</tbody></table>
</details>
</div>
<ul>
<li><code>callback</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function" class="type"><Function></a> The function to call when the timer elapses.</li>
<li><code>delay</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a> The number of milliseconds to wait before calling the
<code>callback</code>. <strong>Default:</strong> <code>1</code>.</li>
<li><code>...args</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Data_types" class="type"><any></a> Optional arguments to pass when the <code>callback</code> is called.</li>
<li>Returns: <a href="timers.html#class-timeout" class="type"><Timeout></a> for use with <a href="#cleartimeouttimeout"><code>clearTimeout()</code></a></li>
</ul>
<p>Schedules execution of a one-time <code>callback</code> after <code>delay</code> milliseconds.</p>
<p>The <code>callback</code> will likely not be invoked in precisely <code>delay</code> milliseconds.
Node.js makes no guarantees about the exact timing of when callbacks will fire,
nor of their ordering. The callback will be called as close as possible to the
time specified.</p>
<p>When <code>delay</code> is larger than <code>2147483647</code> or less than <code>1</code>, the <code>delay</code>
will be set to <code>1</code>. Non-integer delays are truncated to an integer.</p>
<p>If <code>callback</code> is not a function, a <a href="errors.html#class-typeerror"><code>TypeError</code></a> will be thrown.</p>
<p>This method has a custom variant for promises that is available using
<a href="#timerspromisessettimeoutdelay-value-options"><code>timersPromises.setTimeout()</code></a>.</p>
</section><section><h3>Cancelling timers<span><a class="mark" href="#cancelling-timers" id="cancelling-timers">#</a></span><a aria-hidden="true" class="legacy" id="timers_cancelling_timers"></a></h3>
<p>The <a href="#setimmediatecallback-args"><code>setImmediate()</code></a>, <a href="#setintervalcallback-delay-args"><code>setInterval()</code></a>, and <a href="#settimeoutcallback-delay-args"><code>setTimeout()</code></a> methods
each return objects that represent the scheduled timers. These can be used to
cancel the timer and prevent it from triggering.</p>
<p>For the promisified variants of <a href="#setimmediatecallback-args"><code>setImmediate()</code></a> and <a href="#settimeoutcallback-delay-args"><code>setTimeout()</code></a>,
an <a href="globals.html#class-abortcontroller"><code>AbortController</code></a> may be used to cancel the timer. When canceled, the
returned Promises will be rejected with an <code>'AbortError'</code>.</p>
<p>For <code>setImmediate()</code>:</p>
<pre class="with-78-chars"><input class="js-flavor-toggle" type="checkbox" checked aria-label="Show modern ES modules syntax"><code class="language-js mjs"><span class="hljs-keyword">import</span> { setImmediate <span class="hljs-keyword">as</span> setImmediatePromise } <span class="hljs-keyword">from</span> <span class="hljs-string">'node:timers/promises'</span>;
<span class="hljs-keyword">const</span> ac = <span class="hljs-keyword">new</span> <span class="hljs-title class_">AbortController</span>();
<span class="hljs-keyword">const</span> signal = ac.<span class="hljs-property">signal</span>;
<span class="hljs-comment">// We do not `await` the promise so `ac.abort()` is called concurrently.</span>
<span class="hljs-title function_">setImmediatePromise</span>(<span class="hljs-string">'foobar'</span>, { signal })
.<span class="hljs-title function_">then</span>(<span class="hljs-variable language_">console</span>.<span class="hljs-property">log</span>)
.<span class="hljs-title function_">catch</span>(<span class="hljs-function">(<span class="hljs-params">err</span>) =></span> {
<span class="hljs-keyword">if</span> (err.<span class="hljs-property">name</span> === <span class="hljs-string">'AbortError'</span>)
<span class="hljs-variable language_">console</span>.<span class="hljs-title function_">error</span>(<span class="hljs-string">'The immediate was aborted'</span>);
});
ac.<span class="hljs-title function_">abort</span>();</code><code class="language-js cjs"><span class="hljs-keyword">const</span> { <span class="hljs-attr">setImmediate</span>: setImmediatePromise } = <span class="hljs-built_in">require</span>(<span class="hljs-string">'node:timers/promises'</span>);
<span class="hljs-keyword">const</span> ac = <span class="hljs-keyword">new</span> <span class="hljs-title class_">AbortController</span>();
<span class="hljs-keyword">const</span> signal = ac.<span class="hljs-property">signal</span>;
<span class="hljs-title function_">setImmediatePromise</span>(<span class="hljs-string">'foobar'</span>, { signal })
.<span class="hljs-title function_">then</span>(<span class="hljs-variable language_">console</span>.<span class="hljs-property">log</span>)
.<span class="hljs-title function_">catch</span>(<span class="hljs-function">(<span class="hljs-params">err</span>) =></span> {
<span class="hljs-keyword">if</span> (err.<span class="hljs-property">name</span> === <span class="hljs-string">'AbortError'</span>)
<span class="hljs-variable language_">console</span>.<span class="hljs-title function_">error</span>(<span class="hljs-string">'The immediate was aborted'</span>);
});
ac.<span class="hljs-title function_">abort</span>();</code><button class="copy-button">copy</button></pre>
<p>For <code>setTimeout()</code>:</p>
<pre class="with-74-chars"><input class="js-flavor-toggle" type="checkbox" checked aria-label="Show modern ES modules syntax"><code class="language-js mjs"><span class="hljs-keyword">import</span> { <span class="hljs-built_in">setTimeout</span> <span class="hljs-keyword">as</span> setTimeoutPromise } <span class="hljs-keyword">from</span> <span class="hljs-string">'node:timers/promises'</span>;
<span class="hljs-keyword">const</span> ac = <span class="hljs-keyword">new</span> <span class="hljs-title class_">AbortController</span>();
<span class="hljs-keyword">const</span> signal = ac.<span class="hljs-property">signal</span>;
<span class="hljs-comment">// We do not `await` the promise so `ac.abort()` is called concurrently.</span>
<span class="hljs-title function_">setTimeoutPromise</span>(<span class="hljs-number">1000</span>, <span class="hljs-string">'foobar'</span>, { signal })
.<span class="hljs-title function_">then</span>(<span class="hljs-variable language_">console</span>.<span class="hljs-property">log</span>)
.<span class="hljs-title function_">catch</span>(<span class="hljs-function">(<span class="hljs-params">err</span>) =></span> {
<span class="hljs-keyword">if</span> (err.<span class="hljs-property">name</span> === <span class="hljs-string">'AbortError'</span>)
<span class="hljs-variable language_">console</span>.<span class="hljs-title function_">error</span>(<span class="hljs-string">'The timeout was aborted'</span>);
});
ac.<span class="hljs-title function_">abort</span>();</code><code class="language-js cjs"><span class="hljs-keyword">const</span> { <span class="hljs-attr">setTimeout</span>: setTimeoutPromise } = <span class="hljs-built_in">require</span>(<span class="hljs-string">'node:timers/promises'</span>);
<span class="hljs-keyword">const</span> ac = <span class="hljs-keyword">new</span> <span class="hljs-title class_">AbortController</span>();
<span class="hljs-keyword">const</span> signal = ac.<span class="hljs-property">signal</span>;
<span class="hljs-title function_">setTimeoutPromise</span>(<span class="hljs-number">1000</span>, <span class="hljs-string">'foobar'</span>, { signal })
.<span class="hljs-title function_">then</span>(<span class="hljs-variable language_">console</span>.<span class="hljs-property">log</span>)
.<span class="hljs-title function_">catch</span>(<span class="hljs-function">(<span class="hljs-params">err</span>) =></span> {
<span class="hljs-keyword">if</span> (err.<span class="hljs-property">name</span> === <span class="hljs-string">'AbortError'</span>)
<span class="hljs-variable language_">console</span>.<span class="hljs-title function_">error</span>(<span class="hljs-string">'The timeout was aborted'</span>);
});
ac.<span class="hljs-title function_">abort</span>();</code><button class="copy-button">copy</button></pre>
<h4><code>clearImmediate(immediate)</code><span><a class="mark" href="#clearimmediateimmediate" id="clearimmediateimmediate">#</a></span><a aria-hidden="true" class="legacy" id="timers_clearimmediate_immediate"></a></h4>
<div class="api_metadata">
<span>Added in: v0.9.1</span>
</div>
<ul>
<li><code>immediate</code> <a href="timers.html#class-immediate" class="type"><Immediate></a> An <code>Immediate</code> object as returned by
<a href="#setimmediatecallback-args"><code>setImmediate()</code></a>.</li>
</ul>
<p>Cancels an <code>Immediate</code> object created by <a href="#setimmediatecallback-args"><code>setImmediate()</code></a>.</p>
<h4><code>clearInterval(timeout)</code><span><a class="mark" href="#clearintervaltimeout" id="clearintervaltimeout">#</a></span><a aria-hidden="true" class="legacy" id="timers_clearinterval_timeout"></a></h4>
<div class="api_metadata">
<span>Added in: v0.0.1</span>
</div>
<ul>
<li><code>timeout</code> <a href="timers.html#class-timeout" class="type"><Timeout></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a> A <code>Timeout</code> object as returned by <a href="#setintervalcallback-delay-args"><code>setInterval()</code></a>
or the <a href="#timeoutsymboltoprimitive">primitive</a> of the <code>Timeout</code> object as a string or a number.</li>
</ul>
<p>Cancels a <code>Timeout</code> object created by <a href="#setintervalcallback-delay-args"><code>setInterval()</code></a>.</p>
<h4><code>clearTimeout(timeout)</code><span><a class="mark" href="#cleartimeouttimeout" id="cleartimeouttimeout">#</a></span><a aria-hidden="true" class="legacy" id="timers_cleartimeout_timeout"></a></h4>
<div class="api_metadata">
<span>Added in: v0.0.1</span>
</div>
<ul>
<li><code>timeout</code> <a href="timers.html#class-timeout" class="type"><Timeout></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a> A <code>Timeout</code> object as returned by <a href="#settimeoutcallback-delay-args"><code>setTimeout()</code></a>
or the <a href="#timeoutsymboltoprimitive">primitive</a> of the <code>Timeout</code> object as a string or a number.</li>
</ul>
<p>Cancels a <code>Timeout</code> object created by <a href="#settimeoutcallback-delay-args"><code>setTimeout()</code></a>.</p>
</section><section><h3>Timers Promises API<span><a class="mark" href="#timers-promises-api" id="timers-promises-api">#</a></span><a aria-hidden="true" class="legacy" id="timers_timers_promises_api"></a></h3>
<div class="api_metadata">
<details class="changelog"><summary>History</summary>
<table>
<tbody><tr><th>Version</th><th>Changes</th></tr>
<tr><td>v16.0.0</td>
<td><p>Graduated from experimental.</p></td></tr>
<tr><td>v15.0.0</td>
<td><p><span>Added in: v15.0.0</span></p></td></tr>
</tbody></table>
</details>
</div>
<p>The <code>timers/promises</code> API provides an alternative set of timer functions
that return <code>Promise</code> objects. The API is accessible via
<code>require('node:timers/promises')</code>.</p>
<pre class="with-13-chars"><input class="js-flavor-toggle" type="checkbox" checked aria-label="Show modern ES modules syntax"><code class="language-js mjs"><span class="hljs-keyword">import</span> {
<span class="hljs-built_in">setTimeout</span>,
setImmediate,
<span class="hljs-built_in">setInterval</span>,
} <span class="hljs-keyword">from</span> <span class="hljs-string">'node:timers/promises'</span>;</code><code class="language-js cjs"><span class="hljs-keyword">const</span> {
<span class="hljs-built_in">setTimeout</span>,
setImmediate,
<span class="hljs-built_in">setInterval</span>,
} = <span class="hljs-built_in">require</span>(<span class="hljs-string">'node:timers/promises'</span>);</code><button class="copy-button">copy</button></pre>
<h4><code>timersPromises.setTimeout([delay[, value[, options]]])</code><span><a class="mark" href="#timerspromisessettimeoutdelay-value-options" id="timerspromisessettimeoutdelay-value-options">#</a></span><a aria-hidden="true" class="legacy" id="timers_timerspromises_settimeout_delay_value_options"></a></h4>
<div class="api_metadata">
<span>Added in: v15.0.0</span>
</div>
<ul>
<li><code>delay</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a> The number of milliseconds to wait before fulfilling the
promise. <strong>Default:</strong> <code>1</code>.</li>
<li><code>value</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Data_types" class="type"><any></a> A value with which the promise is fulfilled.</li>
<li><code>options</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a>
<ul>
<li><code>ref</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Boolean_type" class="type"><boolean></a> Set to <code>false</code> to indicate that the scheduled <code>Timeout</code>
should not require the Node.js event loop to remain active.
<strong>Default:</strong> <code>true</code>.</li>
<li><code>signal</code> <a href="globals.html#class-abortsignal" class="type"><AbortSignal></a> An optional <code>AbortSignal</code> that can be used to
cancel the scheduled <code>Timeout</code>.</li>
</ul>
</li>
</ul>
<pre class="with-13-chars"><input class="js-flavor-toggle" type="checkbox" checked aria-label="Show modern ES modules syntax"><code class="language-js mjs"><span class="hljs-keyword">import</span> {
<span class="hljs-built_in">setTimeout</span>,
} <span class="hljs-keyword">from</span> <span class="hljs-string">'node:timers/promises'</span>;
<span class="hljs-keyword">const</span> res = <span class="hljs-keyword">await</span> <span class="hljs-built_in">setTimeout</span>(<span class="hljs-number">100</span>, <span class="hljs-string">'result'</span>);
<span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(res); <span class="hljs-comment">// Prints 'result'</span></code><code class="language-js cjs"><span class="hljs-keyword">const</span> {
<span class="hljs-built_in">setTimeout</span>,
} = <span class="hljs-built_in">require</span>(<span class="hljs-string">'node:timers/promises'</span>);
<span class="hljs-built_in">setTimeout</span>(<span class="hljs-number">100</span>, <span class="hljs-string">'result'</span>).<span class="hljs-title function_">then</span>(<span class="hljs-function">(<span class="hljs-params">res</span>) =></span> {
<span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(res); <span class="hljs-comment">// Prints 'result'</span>
});</code><button class="copy-button">copy</button></pre>
<h4><code>timersPromises.setImmediate([value[, options]])</code><span><a class="mark" href="#timerspromisessetimmediatevalue-options" id="timerspromisessetimmediatevalue-options">#</a></span><a aria-hidden="true" class="legacy" id="timers_timerspromises_setimmediate_value_options"></a></h4>
<div class="api_metadata">
<span>Added in: v15.0.0</span>
</div>
<ul>
<li><code>value</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Data_types" class="type"><any></a> A value with which the promise is fulfilled.</li>
<li><code>options</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a>
<ul>
<li><code>ref</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Boolean_type" class="type"><boolean></a> Set to <code>false</code> to indicate that the scheduled <code>Immediate</code>
should not require the Node.js event loop to remain active.
<strong>Default:</strong> <code>true</code>.</li>
<li><code>signal</code> <a href="globals.html#class-abortsignal" class="type"><AbortSignal></a> An optional <code>AbortSignal</code> that can be used to
cancel the scheduled <code>Immediate</code>.</li>
</ul>
</li>
</ul>
<pre class="with-15-chars"><input class="js-flavor-toggle" type="checkbox" checked aria-label="Show modern ES modules syntax"><code class="language-js mjs"><span class="hljs-keyword">import</span> {
setImmediate,
} <span class="hljs-keyword">from</span> <span class="hljs-string">'node:timers/promises'</span>;
<span class="hljs-keyword">const</span> res = <span class="hljs-keyword">await</span> <span class="hljs-title function_">setImmediate</span>(<span class="hljs-string">'result'</span>);
<span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(res); <span class="hljs-comment">// Prints 'result'</span></code><code class="language-js cjs"><span class="hljs-keyword">const</span> {
setImmediate,
} = <span class="hljs-built_in">require</span>(<span class="hljs-string">'node:timers/promises'</span>);
<span class="hljs-title function_">setImmediate</span>(<span class="hljs-string">'result'</span>).<span class="hljs-title function_">then</span>(<span class="hljs-function">(<span class="hljs-params">res</span>) =></span> {
<span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(res); <span class="hljs-comment">// Prints 'result'</span>
});</code><button class="copy-button">copy</button></pre>
<h4><code>timersPromises.setInterval([delay[, value[, options]]])</code><span><a class="mark" href="#timerspromisessetintervaldelay-value-options" id="timerspromisessetintervaldelay-value-options">#</a></span><a aria-hidden="true" class="legacy" id="timers_timerspromises_setinterval_delay_value_options"></a></h4>
<div class="api_metadata">
<span>Added in: v15.9.0</span>
</div>
<p>Returns an async iterator that generates values in an interval of <code>delay</code> ms.
If <code>ref</code> is <code>true</code>, you need to call <code>next()</code> of async iterator explicitly
or implicitly to keep the event loop alive.</p>
<ul>
<li><code>delay</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a> The number of milliseconds to wait between iterations.
<strong>Default:</strong> <code>1</code>.</li>
<li><code>value</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Data_types" class="type"><any></a> A value with which the iterator returns.</li>
<li><code>options</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a>
<ul>
<li><code>ref</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Boolean_type" class="type"><boolean></a> Set to <code>false</code> to indicate that the scheduled <code>Timeout</code>
between iterations should not require the Node.js event loop to
remain active.
<strong>Default:</strong> <code>true</code>.</li>
<li><code>signal</code> <a href="globals.html#class-abortsignal" class="type"><AbortSignal></a> An optional <code>AbortSignal</code> that can be used to
cancel the scheduled <code>Timeout</code> between operations.</li>
</ul>
</li>
</ul>
<pre class="with-14-chars"><input class="js-flavor-toggle" type="checkbox" checked aria-label="Show modern ES modules syntax"><code class="language-js mjs"><span class="hljs-keyword">import</span> {
<span class="hljs-built_in">setInterval</span>,
} <span class="hljs-keyword">from</span> <span class="hljs-string">'node:timers/promises'</span>;
<span class="hljs-keyword">const</span> interval = <span class="hljs-number">100</span>;
<span class="hljs-keyword">for</span> <span class="hljs-title function_">await</span> (<span class="hljs-keyword">const</span> startTime <span class="hljs-keyword">of</span> <span class="hljs-built_in">setInterval</span>(interval, <span class="hljs-title class_">Date</span>.<span class="hljs-title function_">now</span>())) {
<span class="hljs-keyword">const</span> now = <span class="hljs-title class_">Date</span>.<span class="hljs-title function_">now</span>();
<span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(now);
<span class="hljs-keyword">if</span> ((now - startTime) > <span class="hljs-number">1000</span>)
<span class="hljs-keyword">break</span>;
}
<span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(<span class="hljs-title class_">Date</span>.<span class="hljs-title function_">now</span>());</code><code class="language-js cjs"><span class="hljs-keyword">const</span> {
<span class="hljs-built_in">setInterval</span>,
} = <span class="hljs-built_in">require</span>(<span class="hljs-string">'node:timers/promises'</span>);
<span class="hljs-keyword">const</span> interval = <span class="hljs-number">100</span>;
(<span class="hljs-keyword">async</span> <span class="hljs-keyword">function</span>(<span class="hljs-params"></span>) {
<span class="hljs-keyword">for</span> <span class="hljs-title function_">await</span> (<span class="hljs-keyword">const</span> startTime <span class="hljs-keyword">of</span> <span class="hljs-built_in">setInterval</span>(interval, <span class="hljs-title class_">Date</span>.<span class="hljs-title function_">now</span>())) {
<span class="hljs-keyword">const</span> now = <span class="hljs-title class_">Date</span>.<span class="hljs-title function_">now</span>();
<span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(now);
<span class="hljs-keyword">if</span> ((now - startTime) > <span class="hljs-number">1000</span>)
<span class="hljs-keyword">break</span>;
}
<span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(<span class="hljs-title class_">Date</span>.<span class="hljs-title function_">now</span>());
})();</code><button class="copy-button">copy</button></pre>
<h4><code>timersPromises.scheduler.wait(delay[, options])</code><span><a class="mark" href="#timerspromisesschedulerwaitdelay-options" id="timerspromisesschedulerwaitdelay-options">#</a></span><a aria-hidden="true" class="legacy" id="timers_timerspromises_scheduler_wait_delay_options"></a></h4>
<div class="api_metadata">
<span>Added in: v17.3.0, v16.14.0</span>
</div>
<p></p><div class="api_stability api_stability_1"><a href="documentation.html#stability-index">Stability: 1</a> - Experimental</div><p></p>
<ul>
<li><code>delay</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a> The number of milliseconds to wait before resolving the
promise.</li>
<li><code>options</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a>
<ul>
<li><code>ref</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Boolean_type" class="type"><boolean></a> Set to <code>false</code> to indicate that the scheduled <code>Timeout</code>
should not require the Node.js event loop to remain active.
<strong>Default:</strong> <code>true</code>.</li>
<li><code>signal</code> <a href="globals.html#class-abortsignal" class="type"><AbortSignal></a> An optional <code>AbortSignal</code> that can be used to
cancel waiting.</li>
</ul>
</li>
<li>Returns: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Promise" class="type"><Promise></a></li>
</ul>
<p>An experimental API defined by the <a href="https://github.com/WICG/scheduling-apis">Scheduling APIs</a> draft specification
being developed as a standard Web Platform API.</p>
<p>Calling <code>timersPromises.scheduler.wait(delay, options)</code> is equivalent
to calling <code>timersPromises.setTimeout(delay, undefined, options)</code>.</p>
<pre><code class="language-js mjs"><span class="hljs-keyword">import</span> { scheduler } <span class="hljs-keyword">from</span> <span class="hljs-string">'node:timers/promises'</span>;
<span class="hljs-keyword">await</span> scheduler.<span class="hljs-title function_">wait</span>(<span class="hljs-number">1000</span>); <span class="hljs-comment">// Wait one second before continuing</span></code> <button class="copy-button">copy</button></pre>
<h4><code>timersPromises.scheduler.yield()</code><span><a class="mark" href="#timerspromisesscheduleryield" id="timerspromisesscheduleryield">#</a></span><a aria-hidden="true" class="legacy" id="timers_timerspromises_scheduler_yield"></a></h4>
<div class="api_metadata">
<span>Added in: v17.3.0, v16.14.0</span>
</div>
<p></p><div class="api_stability api_stability_1"><a href="documentation.html#stability-index">Stability: 1</a> - Experimental</div><p></p>
<ul>
<li>Returns: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Promise" class="type"><Promise></a></li>
</ul>
<p>An experimental API defined by the <a href="https://github.com/WICG/scheduling-apis">Scheduling APIs</a> draft specification
being developed as a standard Web Platform API.</p>
<p>Calling <code>timersPromises.scheduler.yield()</code> is equivalent to calling
<code>timersPromises.setImmediate()</code> with no arguments.</p></section>
<!-- API END -->
</div>
</div>
</div>
</body>
</html>
|
