checking multiple conditions asynchronously

async_conditioning.js

var bools = {};
function check1(){
  // do something
  bools['check1'] = condition1;
  finalChek();
}

function check2(){
  // do other things
  bool['check2'] = condition2);
  finalCheck();
}

function finalCheck(){
  if(bools['check1'] != undefined && bools['check2'] != undefined){
    var finalBool = true;
    for(var attr in bools){
      finalBool &= bools[attr];
    }
    if(finalBool){
      //all true
    }else{
      //at least one false
    }
  }
}

// start somthing async
async_function(check1);
async_function(check2);