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JavaScript

Posted by Daniel Coulter
Daniel Coulter
4,691 Points

My solution for the Refactor Challenge

let html = ''; const color = () => { return Math.floor(Math.random() * 256);} let randomRGB;

for ( let i = 1; i < 11; i++) { randomRGB = rgb( ${color()}, ${color()}, ${color()} ); html += <div style="background-color: ${randomRGB}">${i}</div>; }

document.querySelector('main').innerHTML = html;

1 Answer

Charlie Palmer
Charlie Palmer
15,445 Points
Charlie Palmer
Charlie Palmer
15,445 Points 
const eightBit = () => Math.floor(Math.random() * 256);
const genRGB = () => `rgb(${eightBit()}, ${eightBit()}, ${eightBit()})`;
const genHTML = (length) => {
  let html = '';
  for(let i = 0; i > length; i++) {
    html += `<div style="background-color: ${genRGB()}">${i}</div>`
  }
  return html;
}
document.querySelector('main').innerHTML = genHTML(10);

haven't actually tested to see if it works but probably should. with arrow functions, you can skip the curly braces if the function can make a return in one line, you also won't have to use the return keyword as it should return the value returned from the method. I'm pretty sure instead of using the for-loop you could use a syntax like this

//Array(length).forEach((element, index) => {your function});
Array(10).forEach((x, I) => {
  html += `<div style="background-color: ${genRGB()}">${i}</div>`;
});

however, I'm pretty sure that is bad practice unless you're trying to create and fill an array with data, the syntax might be a little bit wrong too but I don't think so.

so it could look like this:

const eightBit = () => Math.floor(Math.random() * 256);
const genRGB = () => `rgb(${eightBit()}, ${eightBit()}, ${eightBit()})`;
const genHTML = (length) => {
  let html = '';
  Array(length).forEach((x, i) => {
  html += `<div style="background-color: ${genRGB()}">${i}</div>`;
});
  return html;
}
document.querySelector('main').innerHTML = genHTML(10);

I'm sure Steven Parker will correct me if I'm wrong :)

Steven Parker
Steven Parker
231,261 Points
Steven Parker
Steven Parker
231,261 Points

Only because you invoked me.   :wink:

  • in the first example, the "for" loop test needs to be "i < length" (instead of greater) for it to run
  • the second example has a capital "I" parameter but references lower-case "i"
  • Array() allocates empty slots, so .forEach won't work (but Array(n).fill(0).forEach() would)

And while it can work, creating an otherwise unused array simply to use forEach instead of for is pretty bizarre and less efficient (17% slower according to JSBench.me).   :see_no_evil:

And did Daniel actually ask a question? I thought he might just be sharing.