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So in the last lesson, we said that we were going to shorten these five lines of code using the Swift
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ternary operator.
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So the way of the ternary operator works is that we have a condition, just as we have conditions
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in if statements,
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we have this condition and we check to see if it's true or if it's false. If it's true,
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then we set this value to a particular value if it's true.
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And if it's not true, then we set it to something else.
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So let's try and convert our five lines of code to this format.
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So the value in this case is the cell.accessoryType and we're going to set it to equal the condition
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which is the same as what's between our If statement and our opening bracket.
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So whether if item.done is equal to true. And if it is true, then the cell.accessoryType is going
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to be set to .checkmark. But otherwise, if it's not true, then the cell.accessoryType is going to
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be set to equal .none.
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And that's a one line expression that does exactly the same thing as all of these lines.
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And we can make it even shorter by getting rid of this check.
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So this line now reads set the cell's accessoryType depending on whether the item.done is true.
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If it is true, then set it to .checkmark.
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And if it's not true, then set it to .none.
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So depending on how much you've used this ternary operator or how much you've seen it used, you'll
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begin to get comfortable with this expression.
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And admittedly, when you first see it, it looks like magic, right?
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It just doesn't look like a real code because it's so short and it's, you know, some would argue not as
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explicit as this. Now, because we've come such a long way, and a big shout out to everybody who's been
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following along
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up till now, you've amassed a lot of knowledge. And previously in my code, I've tried to make the code
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as explicit as humanly possible even though sometimes it's very, very cumbersome.
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Now, as we're getting into the intermediate and advanced stages, I want to make sure that you learn and
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you can understand some of these ways that programmers will express their code to cut down on the number
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of lines and make that code look more succinct and more elegant.
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So when you come across something like this in the future, you'll no longer be confused as to what it
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means.
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So, now I can safely delete all of that.
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And if we run our app, let's see if despite deleting something like 10 lines of code, whether if our app
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still works exactly the same,
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let's just confirm.
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So I can safely confirm that our app works exactly the same as before.
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Even though we're making everything super short and super succinct, it's still behaving exactly as we
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wanted to.