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JavaScript JavaScript Loops, Arrays and Objects Simplify Repetitive Tasks with Loops The Refactor Challenge, Part 2

Posted by Daniel Hurd
Daniel Hurd
12,987 Points

Why add a variable for randomColor() in the for loop?

Hi Dave McFarland (or anyone else who knows)!

Thanks SO much for this course, it's very helpful. In The Refactoring Challenge part 2, here's the for loop:

for (var i = 1; i <= 10; i +=1) { 
  rgbColor = randomColor();
  html += '<div style="background-color:' + rgbColor + '"></div>';
}

So, why add a variable for the randomColor function? Wouldn't the below code be better?

for (var i = 1; i <= 10; i +=1) { 
  html += '<div style="background-color:' + randomColor() + '"></div>';
}

I'm curious, is adding a function to a concatenated string less stable, or maybe it's just better practice to call a function with a variable instead of the function itself? Thank you in advance!!

-Daniel H

2 Answers

Dave McFarland
STAFF
Dave McFarland
Treehouse Teacher
Dave McFarland
Dave McFarland
Treehouse Teacher

Great question Daniel Hurd

There's more than one way to write a program. The second piece of code you list is excellent: 

for (var i = 1; i <= 10; i +=1) { 
  html += '<div style="background-color:' + randomColor() + '"></div>';
}

It's shorter and more concise, and probably the better way to write it. I choose to use a variable just to make sure that the code was easy to understand (at least that's what I hope!)

You can certainly insert function calls within string concatenation (as long as the function returns a STRING, of course). That's a very common practice. Good job.

Daniel Hurd
Daniel Hurd
12,987 Points

Dave McFarland -

Okay great, thank you! Wanted to ensure I wasn't missing something important. It's funny, I only had the idea to use the function within the string from the example of the other function you wrote. Seeing both options helps!

-Daniel H

Nelson Lourenco
Nelson Lourenco
1,766 Points
Nelson Lourenco
Nelson Lourenco
1,766 Points

I had the same question, thanks Dave!