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Timer: setTimeout and function call

function tick() {
seconds_lapsed++; // Break point.
}
function countdown() {
while(!stopped || !is_paused()){
setTimeout(tick, 1000); // 1 second.
show_counter();
}
}
Could you tell me why the interpreter doesn't stop at the breakpoint? The while loop works, hava a look at the screenshot.

The while loop is a "busy" loop, i.e. it keeps the JavaScript engine busy, so it will not process anything that is waiting in one of its event/job queues. This means that the user interface does not get updated, no input can be processed, and events produced by setTimeout are not consumed. In this example, tick can only get executed if the currently running code finishes. So the while loop must end first.
You should let tick execute, and only then check the condition:
var stopped = true;
var seconds_lapsed = 0;
document.querySelector("button").addEventListener("click", function() {
stopped = !stopped;
seconds_lapsed = 0;
this.textContent = stopped ? "Start" : "Stop";
if (!stopped) countdown();
});
function show_counter() {
document.querySelector("span").textContent = seconds_lapsed;
}
function is_paused() {
return document.querySelector("input").checked;
}
function tick() {
seconds_lapsed++;
}
function countdown() {
show_counter();
setTimeout(function () {
if (stopped) return; // stop the loop
if (!is_paused()) tick();
countdown(); // <--- this is the "loop"
}, 1000);
}
Seconds elapsed: <span>0</span><br>
<input type="checkbox">Paused<br>
<button>Start</button>

the following example might help you accomplish what you are after. Distinguish between setInterval() and setTimeout()
Basically the docs say:
setTimeout executes a function or specified piece of code once the timer expires.
setInterval repeatedly calls a function or executes a code snippet, with a fixed time delay between each call.
So if you use setInterval you don't need a while loop inside because it is already called "repeatedly"
var counter = $('#counter');
var stopped = false;
var seconds_lapsed=0;
var myInterval;
function tick() {
if(stopped) {
clearInterval(myInterval);
show_counter('FINISHED');
return;
}
show_counter(seconds_lapsed++);
}
function show_counter(message){
counter.html(message);
}
function countdown() {
myInterval = setInterval(tick, 1000);
}
function endCountdown(timeout) {
let timeoutId = setTimeout(function(){
stopped = true;
clearTimeout(timeoutId)
}, timeout);
}
countdown(); // start the countdown
endCountdown(5000); // ends the countdown after 5000 ms => 5sec
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<div id="counter">counter</div>

Call a function max once in a sec

I have a function that is used to send messages and that is called multiple times in a sec.
But I want to call that function once a sec and delay other calls of that function with another 1-second of the previous call.
So that only that function run in the background and called once in a second, no matters how many times it is called it will delay each call to one second ahead.
For example:
function foo(a) {
console.log(a)
}
foo('one');
foo('two');
foo('three');
in the above example, foo is called three times within a sec but I want to have it called like after the 1 second it should return "one" after 2 seconds it should return 'second' and so on and it should be asynchronous.
How can I do this?
The technology I am using is Javascript.
Thanks

Well this is the first thing I came up with - perhaps it's crude.
var queuedUpCalls = [];
var currentlyProcessingCall = false;
function foo(a) {
if (currentlyProcessingCall) {
queuedUpCalls.push(a);
return;
}
currentlyProcessingCall = true;
setTimeout(function(){
console.log(a);
currentlyProcessingCall = false;
if (queuedUpCalls.length) {
var nextCallArg = queuedUpCalls.shift();
foo(nextCallArg);
}
},1000);
}
foo('one');
foo('two');
foo('three');
For each call, if you're not currently processing a call, just call setTimeout with a delay of 1000ms. If you are processing a call, save off the argument, and when the setTimeout that you kicked off finishes, process it.
Somewhat improved answer using setInterval:
var queuedUpCalls = [];
var timerId;
function foo(a) {
queuedUpCalls.push(a);
if (timerId) {
return;
}
timerId = setInterval(function(){
if (!queuedUpCalls.length) {
clearInterval(timerId);
timerId = null;
return;
}
var nextCallArg = queuedUpCalls.shift();
console.log(nextCallArg);
}, 1000);
}
foo('one');
foo('two');
foo('three');

Here is a simple queue system, it basically just pushes the functions onto an array, and then splice's them off every second.
const queue = [];
setInterval(function () {
if (!queue.length) return;
const f = queue[0];
queue.splice(0, 1);
f();
}, 1000);
function foo(a) {
queue.push(function () {
console.log(a)
});
}
foo('one');
foo('two');
foo('three');

you could use this to run the main code first and then run some more code a little later.
function firstfunction() {
alert('I am ran first');
setTimeout(function(){ alert('I am ran 3 seconds later') }, 3000);
}
<button onclick="firstfunction();">click me</button>

function foo(a)
{
if (typeof foo.last == 'undefined')
foo.last = Date.now();
var now = Date.now();
if (now - 1000 > foo.time)
foo.last = now;
setTimeout(function()
{
console.log(a);
}, (foo.last += 1000) - now);
}
This will queue each console.log call with intervals of 1 second, the first call will also be delayed by 1 second.

You could do this:
function foo() {
console.log(“ran”);
}
setInterval(foo, 1000);
In the last line, writing foo() without parenthesis is intentional. The line doesn’t work if you add parentheses.

Javascript setInterval function to clear itself?

myInterval = setInterval(function(){
MyFunction();
},50);
function MyFunction()
{
//Can I call clearInterval(myInterval); in here?
}
The interval's not stopping (not being cleared), if what I've coded above is fine then it'll help me look elsewhere for what's causing the problem. Thanks.
EDIT: Let's assume it completes a few intervals before clearInterval is called which removes the need for setTimeout.

As long as you have scope to the saved interval variable, you can cancel it from anywhere.
In an "child" scope:
var myInterval = setInterval(function(){
clearInterval(myInterval);
},50);
In a "sibling" scope:
var myInterval = setInterval(function(){
foo();
},50);
var foo = function () {
clearInterval(myInterval);
};
You could even pass the interval if it would go out of scope:
var someScope = function () {
var myInterval = setInterval(function(){
foo(myInterval);
},50);
};
var foo = function (myInterval) {
clearInterval(myInterval);
};

clearInterval(myInterval);
will do the trick to cancel the Interval whenever you need it.
If you want to immediately cancel after the first call, you should take setTimeout instead. And sure you can call it in the Interval function itself.
var myInterval = setInterval(function() {
if (/* condition here */){
clearInterval(myInterval);
}
}, 50);
see an EXAMPLE here.

var interval = setInterval(function() {
if (condition) clearInterval(interval); // here interval is undefined, but when we call this function it will be defined in this context
}, 50);
Or
var callback = function() { if (condition) clearInterval(interval); }; // here interval is undefined, but when we call this function it will be defined in this context
var interval = setInterval(callback, 50);

From your code what seems you want to do is to run a function and run it again and again until some job is done...
That is actually a task for the setTimeout(), the approach is similar:
var myFunction = function(){
if( stopCondition ) doSomeStuff(); //(do some stuff and don't run it again)
else setTimeout( myFunction, 50 );
}
myFunction(); //immediate first run
Simple as that :)
Of course if you REALLY want to use setInterval for some reason, #jbabey's answer seems to be the best one :)

You can do it by using a trick with window.setTimeout
var Interval = function () {
if (condition) {
//do Stuff
}
else {
window.setTimeout(Interval, 20);
};
};
window.setTimeout(Interval, 20);

Pause JS function from another function

Is there any way I can pause the below set of delayed functions from another function? I want to pause everything for 10 seconds by executing another function.
What I need is something like:
function pause(){
pause sleepLoop() for 10 seconds
}
If it is not possible to pause the below execution, can I kill it?
function game() {
sleepLoop();
}
function sleepLoop() {
loop...
setTimeout('gameActions()',5000);
}
function gameActions() {
actions...
sleepLoop();
}

Store the timer in a variable. Then you can stop it with clearTimeout, and restart it after 10 seconds:
function game() {
sleepLoop();
}
var sleepLoopTimeout;
function sleepLoop() {
gameActions();
sleepLoopTimeout = setTimeout(sleepLoop,5000);
}
function pause(){
clearTimeout(sleepLoopTimeout);
setTimeout(sleepLoop, 10000);
}
function gameActions() {
// Actions
}

var gameTimeout, sleepTimeout;
function game() {
gameTimeout = setTimeout(sleepLoop, 10000); //start in 10 seconds
}
function sleepLoop() {
sleepTimeout = setTimeout(gameActions, 5000); //start in 5 secs
}
function gameActions() {
sleepLoop();
}
//start it off:
game();
Other than the above, I am not sure what you are asking.
To kill (clear) the timeouts:
clearTimeout(gameTimeout);
clearTimeout(sleepTimeout);

var blocked = false;
function loopToBePaused()
{
if (blocked !== false)
{
// will check for blocker every 0.1s
setTimeout(loopToBePaused, 100);
return;
}
// payload
// normal loop now, e.g. every 1s:
setTimeout(loopToBePaused, 1000);
}
// somewhere in code run:
blocked = setTimeout(function() {
// blocking our loop'ed function for 10s
blocked = false;
}, 10000);
// this will block our main loop for 10s

JavaScript setTimeout setInterval within one function

I think I might be overtired but I cannot for the life of me make sense of this, and I think it's due to a lack of knowledge of javascript
var itv=function(){
return setInterval(function(){
sys.puts('interval');
}, 1000);
}
var tout=function(itv){
return setTimeout(function(){
sys.puts('timeout');
clearInterval(itv);
}, 5500);
}
With these two functions I can call
a=tout(itv());
and get a looping timer to run for 5.5 seconds and then exit, essentially.
By my logic, this should work but it simply is not
var dotime=function(){
return setTimeout(function(){
clearInterval(function(){
return setInterval(function(){
sys.puts("interval");
}, 1000);
});
}, 5500);
}
any insight in this matter would be appreciated.

it cannot work because because your setInterval will be called AFTER the timeout! your original approach is correct and you can still wrap this into single function:
var dotime=function(){
var iv = setInterval(function(){
sys.puts("interval");
}, 1000);
return setTimeout(function(){
clearInterval(iv);
}, 5500);
};

I think the mistake you're making is that the function itv doesn't return setInterval(function(){ sys.puts('interval'); }, 1000) it executes setInterval(function(){ sys.puts('interval'); }, 1000) and than returns back an ID that setInterval generates. That ID is then passed to the clearInterval function to stop what setInterval(function(){ sys.puts('interval'); }, 1000) is doing.
Edit: An example of one function that would work.
var dotime=function(){
// Start our interval and save the id
var intervalId = setInterval(function(){
// This will get executed every interval
sys.puts("interval");
}, 1000);
// Start our timout function
setTimeout(function(){
// This will get executed when the timeout happens
clearInterval(intervalId); // Stop the interval from happening anymore
}, 5500);
}

This is another way to write your version, you see that you pass a function to clearInterval, where you should have passed it a timer id.
var dotime=function(){
var g=function(){
var f=function(){
return setInterval(function(){
sys.puts("interval");
}, 1000);
}
clearInterval(f);
}
return setTimeout(g, 5500);
}
To make it work you shoud call the function :
clearInterval(f());
Or, using your version :
var dotime=function(){
return setTimeout(function(){
clearInterval(function(){
return setInterval(function(){
sys.puts("interval");
}, 1000);
}());
}, 5500);
}
Disclaimer : I didn't test this.