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Different Types of Functions in JavaScript

Md. Jamal Uddin on November 03, 2018

Different Types of Functions in JavaScript Photo by Markus Spiske on Unsplash A JavaScript function is a block of code designed to per...

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David Wickes • Nov 4 '18 • Edited

Very comprehensive!

Couple of typos:

Your default parameters examples has ; instead of , between the arguments

const multiply = (a = 2, b = 3, c = 1) => a * b * c;

You're missing a ' on your new Function example:

var sum = new Function('a', 'b', 'return a + b');

(I love that you introduce the Function constructor by the way - hours of fun for everyone there)

Md. Jamal Uddin • Nov 4 '18 • Edited

Bull's eye man! truly I have read my post more than 10 times :) and two of my friends proofread it but no one figured it out. I will be more prepared next time. thanks.

Guillaume Martigny • Nov 3 '18

Nice article. Small comment, on the third arrow function example, when you write :

const noise2 = _ => console.log("Pling");

There's an unused parameter named _ instead of no parameter. Both are valid anyway, just wanted to point out the difference ;)

Md. Jamal Uddin • Nov 3 '18

Yeah! It's intentional. Only for showing variation. Thanks so much for your comment.

victordeflos • Jan 22 '21

i am a beginner in coding i am currently finishing frond end courses and for the final test i need an idea to be able to make some program in react. please help or some page on the web where I could find examples and printed codes. thank you very much

Tamal Anwar Chowdhury • Nov 3 '18

Very in depth and helpful.

Md. Jamal Uddin • Nov 3 '18

Thanks man!😍

Waqar Mohammad • Nov 4 '18

Nice article dude. Your English is great too. Keep it up

Md. Jamal Uddin • Nov 4 '18

Thanks

Thomas Bishop • Aug 31 '19

Very helpful article and admirably free of waffle. Nice work :)

Md. Jamal Uddin • Sep 3 '19

Thanks

Álvaro Cáceres Muñoz • Nov 6 '18

Nice article! You managed to make me understand generators for the first time XD.

By the way, could you please give me a practical use case of the Function consctructor? Thank you

Md. Jamal Uddin • Nov 7 '18

here is an example Function constructor with implementing a class and you know JavaScript class is a syntactic sugar over the function structure.


class Animal {
  constructor(name, energy) {
    this.name = name
    this.energy = energy
  }
  eat(amount) {
    console.log(`${this.name} is eating.`)
    this.energy += amount
  }
  sleep() {
    console.log(`${this.name} is sleeping.`)
    this.energy += length
  }
  play() {
    console.log(`${this.name} is playing.`)
    this.energy -= length
  }
}

const leo = new Animal('Leo', 7)