How do I write an infinite loop that won't crash my browser?

Question

How does one write an infinite loop in javascript that won't crash your browser. I have found two things on the internet regarding infinite loops in javascript...

for(;;){}

and...

while(true){}

the problem with both of these is that the crash my computer... I thought you were able to just put...

Loop;

at the end of the code and it would infinitely loop through the code, but I was wrong, what is the proper way to loop through code infinitely that will not crash my browser?

You can't. An infinite loop in Javascript will always freeze up the browser because it will block the execution of any other Javascript, which is single-threaded. What are you trying to accomplish? — John Wu, Jan 30 '17 at 23:48
"*I have found two things on the internet regarding infinite loops in java*" - did you mean JavaScript? I'm assuming you did, but I didn't want to put words in your mouth by editing without confirmation. — David Thomas, Jan 30 '17 at 23:49
I was trying to find a way to have code repeat until you close your browser. — Joshua Reid, Jan 30 '17 at 23:51
Or you can have a recursive function that calls itself after a `setTimeout`. — charlietfl, Jan 30 '17 at 23:54
Yes, I have. I tried that, but it doesn't work. setInterval(code,timeInMiliSecs); — Joshua Reid, Jan 30 '17 at 23:58
should work fine assuming the interval is long enough for all the code to complete and not overload the call stack... edit question with a [mcve] and you will get more help that way — charlietfl, Jan 31 '17 at 00:03
I'm just trying to test it, but this is the code I have... setInterval(document.write(Date()), 1000); — Joshua Reid, Jan 31 '17 at 00:05

score 4 · Answer 1 · answered Jan 30 '17 at 23:52

If you need to write some Javascript code that takes a long time (up to and including "forever") you should move it out of the main Javascript content and into a WebWorker.

var myWorker = new Worker('worker.js');

This allows you to load the script in worker.js and execute it in a separate context that runs in parallel.

If you just need something to run once and while until the user exits the page (or closes the browser) then just use setInterval:

var intervalID = window.setInterval(myCallback, 500);

function myCallback() {
  // Your code here
}

How do I write an infinite loop that won't crash my browser?

1 Answers1