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Well done!
You have completed Callback Functions in JavaScript!
You have completed Callback Functions in JavaScript!
Preview
In this video, we'll convert our anonymous function into an arrow function.
Arrow Functions
( ) => {
console.log("Hello");
}
( ) => console.log("Good bye");
Checkout this workshop on Arrow Functions for more details and examples.
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Arrow functions are a common way you'll
see anonymous functions being written.
0:00
In this video, we'll convert our
anonymous functions into arrow functions.
0:05
Let's pull out this anonymous function
from the executeCallback function.
0:10
This way, we can see the progression
from a regular anonymous function
0:15
to an arrow function.
0:19
To convert a function
into an arrow function,
0:20
simply remove the function keyword.
0:24
And after the parentheses, add an equal
sign and a greater than symbol,
0:26
this is often called a fat arrow.
0:31
Let's reintroduce the callback
into the executeCallback function.
0:34
Arrow functions have an even shorter
syntax, if there's a single line of code,
0:41
you can remove the curly braces, like so.
0:46
Why not pause the video and
create an arrow function for
0:52
the goodbye anonymous callback?
0:55
How did you do,
it's pretty straightforward,
1:01
remove the keyword, and add the fat arrow.
1:06
You could have gone a step forward and
removed the curly braces too,
1:10
you'd also need to remove the semicolon.
1:17
You need to remove the semicolon
after the console.log statement,
1:22
because it would terminate the line
of code before the last parentheses.
1:26
If the line of code terminated
before the parentheses,
1:31
the executeCallback function
wouldn't get executed.
1:34
Well done, you've created your own
callback function and callback executor,
1:40
and used two styles of
anonymous functions.
1:44
So far, the example we have
used is pretty contrived.
1:47
In the next few sections, we're going to
take a look at some real world examples
1:51
using timers and a document object model.
1:55
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