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JavaScript AJAX Basics (retiring) Programming AJAX AJAX Callbacks

d4rk5un
d4rk5un
2,771 Points

Create callback function challenge

'Create callback function' challenge won't pass if you use an arrow function.

2 Answers

Steven Parker
Steven Parker
231,126 Points

Arrow functions are not intended to be used instead of conventional functions in all situations, and in fact there are some situations where they are specifically not allowed (they cannot be used as constructors, for example). Another difference that often causes confusion is that they don't define internal variables such as "this" like conventional functions do.

For a complete description of the differences, see this MDN page.

d4rk5un
d4rk5un
2,771 Points

Thank you for your answer.

I am aware of what you are saying, the thing is that I can use the arrow functions with the previous examples, but they the tests won't pass if I use them in this particular exercise.

Cheers! K.

Steven Parker
Steven Parker
231,126 Points

Right, and that's probably because this time the function you're passing it to is dependent on one or more of those factors that only conventional functions provide. If you check the documentation for the API, it would hopefully include a warning that arrow functions can't be used there.