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Anonymous Function as Arrow Functions
1:58In this video, we'll convert our anonymous function into an arrow function.
Arrow functions are a common way you'll
see anonymous functions being written.
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In this video, we'll convert our
anonymous functions into arrow functions.
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Let's pull out this anonymous function
from the executeCallback function.
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This way, we can see the progression
from a regular anonymous function
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to an arrow function.
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To convert a function
into an arrow function,
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simply remove the function keyword.
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And after the parentheses, add an equal
sign and a greater than symbol,
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this is often called a fat arrow.
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Let's reintroduce the callback
into the executeCallback function.
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Arrow functions have an even shorter
syntax, if there's a single line of code,
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you can remove the curly braces, like so.
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Why not pause the video and
create an arrow function for
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the goodbye anonymous callback?
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How did you do,
it's pretty straightforward,
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remove the keyword, and add the fat arrow.
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You could have gone a step forward and
removed the curly braces too,
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you'd also need to remove the semicolon.
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You need to remove the semicolon
after the console.log statement,
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because it would terminate the line
of code before the last parentheses.
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If the line of code terminated
before the parentheses,
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the executeCallback function
wouldn't get executed.
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Well done, you've created your own
callback function and callback executor,
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and used two styles of
anonymous functions.
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So far, the example we have
used is pretty contrived.
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In the next few sections, we're going to
take a look at some real world examples
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using timers and a document object model.
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