Return join vs return string [closed]

Question

I saw this example and wondered why anyone would do it:

function a(str) {
  return [
    '<div>',
     str,
    '</div>'
  ].join('');
}

Isn't it an equivalent to the following code and what's the advantages / disadvantages of using just:

function a(str) {
  return '<div>' +
     str +
    '</div>;
}

Thank you.

Answer 1

They're the same thing. Some experiments have shown using the + operator is faster but this will vary between browsers. Not to mention, these kinds of micro-optimizations don't tend to contribute much.

So which one is better? Whichever one you like the most.