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JavaScript Callback Functions in JavaScript Introduction to Callback Functions Anonymous Function as Arrow Functions

Hayden Lau
Hayden Lau
4,186 Points
Posted by Hayden Lau
Hayden Lau
4,186 Points

Why function executeCallback(callback) { callback(); }; did not also get converted into arrow function?

Can someone explain to me in the arrow function tutorial,

They only converted the Print Hello and Print Goodbye into arrow function. but not the function declaration of executeCallBack(callback)?

Below is the code:

function executeCallback(callback) { callback(); };

//Print Hello executeCallback(() => console.log('Hello'));

//Print Goodbye

executeCallback(() => console.log('Goodbye'));

Thanks!

Hayden

1 Answer

Steven Parker
Steven Parker
231,275 Points
Steven Parker
Steven Parker
231,275 Points

The other functions are anonymous, and the conversion of anonymous functions seems to be the point of this lesson.

But the named function could also be written in the "arrow" style:

const executeCallback = callback => callback();

But be aware that arrow functions can't always replace conventional ones, particularly as constructors, class methods, generators, and anywhere "this" or "arguments" are used. For more details, see the MDN page on Arrow Functions.

Hayden Lau
Hayden Lau
4,186 Points
Hayden Lau
Hayden Lau
4,186 Points

Got it. Thanks for the help!