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Turn regular function declarations into arrow function expressions.
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Welcome back.
0:00
How did you do?
0:01
If you had any trouble, don't worry.
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We're going to walk through how to
rewrite each of these functions
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with arrow syntax right now.
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Let's with the first one, addToTen.
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This is a simple function that receives
parameter num, adds num to 10 and
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then returns the sum.
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To begin,
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let's first replace the function keyword
with variable declaration keyword, const.
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Then we add an equal sign, followed by
the parameter that we're passing in.
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But remember, because we're
only passing in one parameter,
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we don't need to enclose
it in parentheses.
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After the parameter we type our arrow
which points to the code inside our
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function.
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Since this function only
includes one line of code,
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we don't need our curly braces and
the entire expression can go on one line.
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We also don't need the return
key word because arrow functions
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will implicitly return the value
of one line functions.
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That was a lot to take in.
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If there were some things you didn't
understand there, no worries.
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I recommend going back and
reviewing the create functions using arrow
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syntax section of this course,
before trying again.
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For our second function,
divideUs, I'm gonna go ahead and
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copy in my solution to this function.
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The process for
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converting this function declaration
to an arrow function expression,
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is almost exactly the same as our first
example, except for one difference.
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Do you know what it is?
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Yep, you got it.
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This function receives two parameters, so
they have to be enclosed with parentheses.
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Here's my solution for
our final function, printMyName.
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Unlike the last two examples,
this function doesn't take any parameters.
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Even so, we still have to notate this by
including an empty set of parentheses
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after the equals sign.
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Also, because this function
contains two lines of code,
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we have to keep our curly braces.
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So there you have it.
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You just converted three regular
function declarations to
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arrow function expressions.
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Great job.
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Let's move on now to our second file,
refactor.js.
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Inside this file, there are three
functions written with arrow syntax.
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Your goal for this part of
the practice session, is to try and
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refactor these functions so they are as
short and concise as the syntax allows.
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Just a hint, one of these might
already be as concise as possible.
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Give this a go and we'll regroup
later to go over the solution.
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