// 2016-12-10 jorge@jorgechamorro.com
// node.js timers are borken: node checktimers.js errs all the time
// But this won't ever err in a browser: copy-paste in any browser's console

(function (ctr,flag,err1,err2) {
  ctr= 0, flag= 0, err1= 0, err2= 0;

  function _1 () { flag= 0 }
  function _2 () { err1+= flag }
  function _3 () { flag= 1 }
  function _4 () { err2+= !flag }

  function loop (t,i) {
    t= 5, i= 20, ctr+= i;
    while (i--) {
      setTimeout(_1, t+=1);
      setTimeout(_2, t+=1);
      setTimeout(_3, t+=1);
      setTimeout(_4, t+=1);
    }
    setTimeout(loop, t+=20);
  }

  function logger (str) {
    str= '['+ ctr+ '] ERR1: '+ err1+ ' ERR2: '+ err2+ '\r';
    try {
      process.stdout.write(str);
    }
    catch (e) {
      console.log(str);
    }
    setTimeout(logger, 333);
  }

  loop(), logger();
})();