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iOS Swift Basics (retired) Control Flow For-In Loop

Posted by Unsubscribed User
Unsubscribed User
355 Points

A for-in-loop Constant

I see that this question has been asked multiple times and yet I still dont understand. In Amits example he uses a constant within a For in loop, why does he do this when the loop will bring out a new result each time it executes or am I misunderstanding.

Thanks

Faizal

1 Answer

Stone Preston
Stone Preston
42,016 Points
Stone Preston
Stone Preston
42,016 Points

the following is an excerpt from the Swift eBook:

for index in 1...5 {
    println("\(index) times 5 is \(index * 5)")
}

In the example above, index is a constant whose value is automatically set at the start of each iteration of the loop. As such, it does not have to be declared before it is used. It is implicitly declared simply by its inclusion in the loop declaration, without the need for a let declaration keyword.

so while yes the value inside the parenthesis is a constant, its value gets automatically set at each iteration of the loop. its kind of a special case constant in a way, since its value does changes during each iteration.