Check if function can be called: Javascript -

i'm trying write javascript function calls dosomething() continuously, long some_condition true. if some_condition becomes false, should check after 5 seconds whether some_condition has again become true, , if not, display error message on screen.

i have of function written, confused whether doing correctly. help.

while (some_condition) {   dosomething();   else {     ??? } 

no, should not use while loop. javascript single threaded, , if have while loop never returns, browser (or javascript environment of choice) become unresponsive.

you need use settimeout schedule function.

function enqueuesomething() {   if (some_condition)     dosomething();     // enqueue ourselves run again without blocking thread of execution     settimeout(enqueuesomething);   else     // wait 5 seconds, try again     settimeout(enqueuesomething, 5000); } 

you'll need maintain state indicates whether you've waiting 5 seconds, , add error-alerting code.