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JavaScript Asynchronous Programming with JavaScript Asynchronous JavaScript with Callbacks Implement a Callback

Rye Zhu
Rye Zhu
5,514 Points
Posted by Rye Zhu
Rye Zhu
5,514 Points

Confused about this part:

Questions about this part:

btn.addEventListener('click', () => { getJSON(astrosUrl, (json) => { json.people.map( person => getJSON(wikiUrl + person.name);
}); }); });

  1. What is the json parameter?

  2. What is map?

  3. What about person? person is not a property of people.

  4. as for getJSON(wikiUrl + person.name): what's with the plus sign? I've never seen parameters separated by a plus sign in functions.

Thanks sm. I'm very confused about this chunk of code.

1 Answer

Steven Parker
Steven Parker
243,200 Points
Steven Parker
Steven Parker
243,200 Points

It sounds like you may be taking this course out of order. This is an ‍Intermediate‍ level course, and assumes you are already familiar with most capabilities of the language, such as:

If you are new to the language, you might want to start with the Beginning JavaScript track.
If you have some experience already, these courses and workshops might help with your specific questions: