You know that you can use the apply method when you want to use an array as a list of parameters:

let nums = [3, 1, 4, 1, 5, 9];

let highest = Math.max.apply(Math, nums);  

If you need to do this a lot, maybe you want to create a new function that expects an array as its parameter:

function max(arr) {  
  return Math.max.apply(Math, arr);

var highest = max(nums);  

An alternative way to do this is to bind that call to apply.

const max = Math.max.apply.bind(Math.max, Math);  

Confused? Here's how it works:

  • Remember that every function has a bind method, so we can call bind on apply.
  • The first parameter to bind should be the context (the this value), of the function being bound. In our case, the function we're binding is Math.max.apply, and when we call that function, we want this to be Math.max. So that's the first parameter to bind.
  • Any subsequent arguments to bind will be "prepended to the arguments provided to the bound function" (MDN). Since we're passing Math, that will be the first parameter to Math.max.apply, which is what we want.
  • The result of all this is a function whose first expected parameter is the second parameter you would pass to apply, that is, the array of parameters.