Simple closures
We will begin by creating a very simple closure that does not accept any arguments and does not return any value. All it does is print Hello World
to the console. Let's take a look at the following code:
let clos1 = { () -> Void in print("Hello World") }
In this example, we create a closure and assign it to the constant clos1
. Since there are no parameters defined between the parentheses, this closure will not accept any parameters. Also, the return type is defined as Void
; therefore, this closure will not return any value. The body of the closure contains one line that prints Hello World
to the console.
There are many ways to use closures; in this example, all we want to do is execute it. We would execute this closure like this: ...
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