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

Posted by Mila Capecchi
Mila Capecchi
4,429 Points

Why does an arrow function works and a function expression doesn't?

Hello,

I wrote the function to get a random RGB value as a function expression with a return command. This is not working for me:

let html = ''; let i = 0 let randomColor = function() { Math.floor(Math.random() * 256); return randomColor; };

function getRGB() { const color = rgb(${randomColor()},${randomColor()},${randomColor()}); return color }

If I change the same function to an arrow function as Mr. Guil did in the solution video, like this:

let randomColor = () => Math.floor(Math.random() * 256);

then the code starts working. Why is this? Is there a problem with my function expression or can't expressions be used for this situation?

Thanks for your help.

2 Answers

Mila Capecchi
Mila Capecchi
4,429 Points
Mila Capecchi
Mila Capecchi
4,429 Points

Hi Zaid,

Thank you for your answer. I get it now.

Zaid Khan
Zaid Khan
12,769 Points
Zaid Khan
Zaid Khan
12,769 Points

Hi Mila Capecchi

It does work, you just don't return randomColor because you are storing your function in that variable. return what's inside the function.

Like this:

let randomColor = function(){
     return Math.floor(Math.random() * 256);
}

function getRGB() { 
  const color = `rgb(${randomColor()},${randomColor()},${randomColor()})`; 
  return color; 
}
  console.log(getRGB());

Also, it's a good practice to wrap your code around 3 backticks ``` Like the way I did. It's much easier to understand the code.