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JavaScript

Brandi Apetsi
Brandi Apetsi
4,810 Points
Posted by Brandi Apetsi
Brandi Apetsi
4,810 Points

Question about line 45 of Practice Template Literals solution

I understand everything except the .join('') on line 45. Can you explain what is being joined?

1 Answer

kevinardo
seal-mask
.a{fill-rule:evenodd;}techdegree
kevinardo
Treehouse Project Reviewer
kevinardo
.a{fill-rule:evenodd;}techdegree
kevinardo
Treehouse Project Reviewer

Hi Brandi!

Because map() method returns an array, the two planets that get created by createPlanetHTML(planet) inside .map() are then returned as an array, and that array is then presented to us with document.querySelector('body').innerHTML

If you play around a bit and remove the .join(''), you can see the comma ( , ) in the browser, right after the first planet. You can try and write other stuff as a string inside of .join() method. Anyhow, .join() is used here to join the two arrays and leave nothing between them, therefore the empty string in the method.

If you want to dive deeper, check out the methods on MDN: Link to.map() Link to .join()

I hope this helped! Have a great day /Kevin