Event Loop suedo-code

event_loop.js

// my JS code 
// node index.js

index.runCode();

// Node JS event loop

var pendingTimers = [];
var pendingOSTasks = [];
var pendingOperations = [];

function runNextTick(){

      /**
        1) pending setTimeout, setInterval, setImmediate
        2) pending OS tasks ( http server listen )
        3) pending long running tasks ( fs read )
      */ 
      
      return pendingTimers.length || pendingOSTasks.length || pendingOperations.length;
}

while(runNextTick()){
      
      // New `tick`
      
      /**
      
       1) Check for pending timers ( setTimeout and setInterval )
       2) Check for OS tasks and long operations
       3) Pause execution. Continue only when - 
            - pending timer to complete
            - pending os tasks is done
            - pending operation is done
       4) Look for pending timers ( setImmediate )
       5) Handle any `close` events
       
      */
}




// exists back to terminal