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JavaScript Displaying the Content

William MacNish
William MacNish
11,709 Points

Coded a map function that doesn't generate commas, why?

I wrote alternate code for the generateOptions() function, and it doesn't produce commas. Why is that?

function generateOptions(data) { data.map( (entry) => { select.innerHTML += <option value="${entry}">${entry}</option>; }); }

1 Answer

Travis Alstrand
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.a{fill-rule:evenodd;}techdegree seal-36
Travis Alstrand
Treehouse Project Reviewer

Hey William MacNish ! :wave:

In JavaScript, Array.map() is used to transform each element of an array and return a new array.

In your code, you're not using the returned array but instead appending directly to innerHTML. This means that no automatic separators (like commas) are added between the options.

If you're wanting commas in your select.innerHTML, you'll need to manually add them, but I'm not 100% sure of why / where you're wanting or expecting commas here.

I hope this helps and makes sense, if not, or if you'd like to explain where you're wanting commas feel free to reply :smiley: