JAVASCRIPT

higher order function

// A function that returns a function is called a higher-order function.

/*
In this example, we are returning a function from another function - 
We can return a function because functions in JavaScript are 
treated as values.
*/

function sayHello() {
  return () => {
    console.log("Hello!");
  }
}

higher order function

//Syntactic Sugar for a ForEach loop below; this is part of a form validation
//and basicly goes through every element in the form and logs the id for said
//element. 

function checkRequired(inputArr) {
  //   		|   
  //?       V   High Order Array Method 
  inputArr.forEach(function (input) {
    console.log(input.id)  
  });
}

//! Event Listeners --> This is a higher order functon
form.addEventListener('submit', function (e) {
  e.preventDefault();
  //passing in array of arguments to be checked
  checkRequired([username, email, password, password2]); 
});