Push Functions into an Array - Loop through and Splice?

Question

Using Javascript i need to be able to:

1: Push a certain amount of the same function (with a different parameter in each) into an array.

2: Then run each function one by one (for this example just an alert of the parameter/number)

3: After each function i need to be able to SPLICE that function out of the array

4: Check the Array Length after everytime - Once the array is empty again - alert the user it is complete

Now i seem to be able to do task 1,2 and 4 but i am sturggling with how to splice out the function from the array after it has run - can anyone help? As i cannot remove the function i am never getting the 'done' alert once all functions have been called

My javascript code so far is:

// Create empty array
var array = [];

// Push functions into array - dynamic amount and could be any amount of functions
array.push(func(1));
array.push(func(2));
array.push(func(3));

// Call array manager function after pushing array
arrayManager();

// Array manager function to splice and detect when finished
function arrayManager() {
    if (array.length < 1) {
        alert("done");
    }
    else {
    //////////////////////////////////
    // << THIS IS WHERE I DON'T KNOW HOW TO SPLICE THE ITEM FROM THE ARRAY
    //////////////////////////////////
    }
}

// Function for array objects - alert passed parameter
function func(num){
    alert(num);
}

Answer 1

First of all you are not pushing functions into the array at the moment, you execute the func instead. To achieve the push your func should look like this:

// Function for array objects - alert passed parameter
function func(num){
  return function(){
    alert(num);
  }
}

Now if your functions are synchronous you could simply iterate over the array

for(var i in arr){
  arr[i]();
}
console.log('done');

If we are dealing with asynchronous functions then they need to have a callback:

// Function for array objects - alert passed parameter
function func(num){
  return function(callback){
    alert(num);
    callback();
  }
}

And then you can either use a counter to run in parallel.

var count = arr.length;
for(var i in arr){
  arr[i](function(){
    if(--count === 0){
      console.log('Done');
    }
  });
}

Or in sequence:

function run(){
  var fn = arr.shift();
  if(!fn){
    console.log('Done');
  } else {
    fn(run);
  }
}
run();