Why first class function

1. Function can be assigned to a variable

const fn = function(name) {
  console.log(name);
};

fn("rogerio bispo");

2. A function can be a value in an Array

const arr = [
  1,
  function(n1, n2) {
    console.log(n1 + n2);
  }
];

arr[1](1, 10);

3. A function can be a value in an object

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const obj = {
  age: 40,
  name: function(name) {
    console.log(name);
  }
};

obj.name("rogerio");

4. Can be passed to a function

const fn = function(name) {
  console.log(name)
}


const fn2 = (fn) => fn("Bispo")
fn2(fn)

5. Can be returned from a function

const fn3 = () => console.log("returned function");

const fn4 = (fn) => fn;
const returnedFunction = fn4(fn3);
returnedFunction();

6. Function can be an IIFE (Immediately Invoked Function Expression)

(() => console.log("IIFE"))();