Execute function queue in javascript

Question

I\'m trying to create a function queue with several functions in it. After the creation i want to execute each function in it\'s turn. But these function have delayed instru

Answer 1

Try utilizing .queue() , .promise() ; see also Change easing functions on animations in jQuery queue

function fun1() {
  return $.Deferred(function(dfd) {
    setTimeout(function() {
      dfd.resolve(1)
    }, 1500)
  }).promise().then(msg)
}

function fun2() {
  return $.Deferred(function(dfd) {
    setTimeout(function() {
      dfd.resolve(2)
    }, 1500)
  }).promise().then(msg)
}

function fun3() {
  return $.Deferred(function(dfd) {
    setTimeout(function() {
      dfd.resolve(3)
    }, 1500)
  }).promise().then(msg)
}

var funqueue = [];
funqueue.push(function() {
  return fun1()
});
funqueue.push(function() {
  return fun2()
});
funqueue.push(function() {
  return fun3()
});

function msg(data) {
   if (data === "complete") console.log(data)
   else $("body").append(data + "
")
}

function executeFunctionQueue(funqueue) {
  var deferred = funqueue.pop();
  return deferred().then(function() {
      // set `this` within `$.queue()` , `.then()` to empty object `{}`,
      // or other object
      return $({}).queue("fun", $.map(funqueue, function(fn) {
        return function(next) {
          // return `next` function in `"fun"` queue
          return fn().then(next)
        }
      })).dequeue("fun").promise("fun")
      .then(function() {
        // return "complete" string when `fun` queue empty
        return "complete"
      })
    });
}

executeFunctionQueue(funqueue)
.then(msg);

---

Alternatively , using $.when()

function executeFunctionQueue(funqueue) {
  return $.when(!!funqueue[funqueue.length - 1] 
                ? funqueue.pop().call().then(function() {
                  return executeFunctionQueue(funqueue)}) 
                : "complete")
}

executeFunctionQueue(funqueue)
.then(function(complete) { 
  console.log(complete) 
});

function fun1() {
  return $.Deferred(function(dfd) {
    setTimeout(function() {
      dfd.resolve(1)
    }, 1500)
  }).promise().then(msg)
}

function fun2() {
  return $.Deferred(function(dfd) {
    setTimeout(function() {
      dfd.resolve(2)
    }, 1500)
  }).promise().then(msg)
}

function fun3() {
  return $.Deferred(function(dfd) {
    setTimeout(function() {
      dfd.resolve(3)
    }, 1500)
  }).promise().then(msg)
}

var funqueue = [];
funqueue.push(function() {
  return fun1()
});
funqueue.push(function() {
  return fun2()
});
funqueue.push(function() {
  return fun3()
});

function msg(data) {
  if (data === "complete") console.log(data)
  else $("body").append(data + "
")
}

function executeFunctionQueue(funqueue) {
  return $.when(!!funqueue[funqueue.length - 1] 
                ? funqueue.pop().call().then(function() {
                  return executeFunctionQueue(funqueue)}) 
                : "complete")
}

executeFunctionQueue(funqueue)
.then(msg);