The closures in Swift are explained with examples

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Closures are a difficult topic to grasp in Swift, but they are simple to grasp if well described. Closures are functional blocks that can be used or passed around in code.

Closures are an old term that is identical to C and Objective-C blocks. Closures are similar to functions, but they are more flexible and have a more streamlined appearance. Closures are nested functions, and they can capture value, as we’ll see later in this article. Closures have the following significant characteristics:

• It can be assign to variables or constants
• It can be added to arrays, dictionaries or sets, among other things.
• Closures can return from other functions or closures
• Receive as function and closure parameters

Syntax

The following is a very clear and clean syntax for closures:

{(parameters) -> return type 
     in
     statements
}

Assign closures to variables or constants

let a = {(b:Int) -> Int
    in
    return b * 5
}

Tuples can be used as parameters in closures, and they can’t have a default value. The closure accepts an integer parameter and returns an integer that has been multiplied…