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Anonymous Functions
2:14In this video, we'll convert our function declaration into an anonymous function.
Another common way you'll encounter and
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write callback functions
is as anonymous functions.
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An anonymous function is
a function without a name.
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In the case of a callback an anonymous
function can be written in place or
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in line where the name of
the function would be.
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Let's convert sayHello into
an anonymous function.
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With practice, you can jump these
steps that I'm going to take.
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But for now, I'll show my work.
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First, I can change my sayHello
function from a function
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declaration to a function
expression by adding a variable,
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sayHello, And
deleting the name of the function.
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Now to convert this function
to an anonymous function,
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I can just get rid of the variable name.
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How do we pass the anonymous function into
the executeCallback without a reference?
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The function doesn't have a name anymore.
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We can write it in place
of the sayHello name.
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We can do that by cutting and
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pasting the anonymous function
over the sayHello name.
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When writing a function like this,
this is also know as inlining or
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writing a function in line.
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It can be more expressive.
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You can clearly see a function
as a parameter here,
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which isn't always obvious
when you use a named function.
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You can see it's a callback, and
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that the function could get executed
at any given point in the future.
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A callback function is more obvious when
it's written as an anonymous function.
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I've got a small challenge for
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you, write another anonymous
function that will print goodbye.
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Pause the video, and
then I'll show you how I did it.
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I can just copy and paste the execute
callback and replace hello with goodbye.
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