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JavaScript JavaScript Loops Working with 'for' Loops The Refactor Challenge – Duplicate Code

Posted by Megha Singh
Megha Singh
6,146 Points

Function Expression : how can we assign a function to a constant?

It looks like the constant variable is assigned a function and its value changes every time the function is called. Aren't constants supposed to have a fixed value?

1 Answer

Peter Vann
Peter Vann
36,427 Points
Peter Vann
Peter Vann
36,427 Points

Functions don't change and therefore they can be declared as constants. They behave the same way every time they are called. The only change is the values passed to the function as parameters.

Three ways to declare functions (all valid):

function add(num1, num2) {
  return num1 + num2;
}

const add = function(num1, num2) {
  return num1 + num2;
}

const add = (num1, num2) => {
  return num1 + num2;
}

The third version uses the ES6 arrow function shorthand syntax.

More info: https://dmitripavlutin.com/6-ways-to-declare-javascript-functions/

I hope that helps (and is not TMI/overwhelming). Happy coding!