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iOS Swift Closures Functions as First Class Citizens Higher Order Functions

Kyaw Kyaw Soe
Kyaw Kyaw Soe
7,528 Points
Posted by Kyaw Kyaw Soe
Kyaw Kyaw Soe
7,528 Points

I don't understand this challenge please give me answer or explain for me Please

I don't understand this challenge please give me answer or explain for me Please

2 Answers

Richard Lu
Richard Lu
20,185 Points
Richard Lu
Richard Lu
20,185 Points

Hi Jo,

The challenge is to build a function that takes in an argument of a function type. The function called differenceBetweenNumbers, it takes 2 integers (Int, Int) and returns another integer (-> Int), and also 2 other integers that act as operands.

So they want a function that takes those types. How does someone approach this? Well it's simple, take a look below:

func mathOperation(operation: (Int, Int) -> (Int), operand1: Int, operand2: Int) -> Int {
   return operation(operand1, operand2)
}

// Usage
let difference = mathOperation(differenceBetweenNumbers, 1, 2)

Hope I've helped. Happy Coding :)

Kyaw Kyaw Soe
Kyaw Kyaw Soe
7,528 Points
Kyaw Kyaw Soe
Kyaw Kyaw Soe
7,528 Points

Thank you so much Richard Lu. Your answer make me understanding very well