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Joseph Maza
9,184 PointsSwift closure: Higher order functions challenge
Having difficulty understanding what this challenge wants from me. I don't know what math operation it wants me to do.
Write a function called mathOperation that takes a math operation (as defined in the editor) as the first input, two integers on which we carry out the math operation, and a return type of Int. The body of the function simply returns the result of the math operation you pass in. Note: We are attempting to build a higher order function so your first parameter must be a function. If you're having trouble, read the Function Types as Parameter Types section in the docs
/**
For this code challenge, let’s define a math operation as a function that
carries out some work on two integers and returns an integer as well. An
example is the function below, differenceBetweenNumbers, which takes two
integers and calculates the difference between the numbers. After calculating,
it returns the difference.
*/
func differenceBetweenNumbers(a: Int, b:Int) -> (Int) {
return a - b }
3 Answers
Holger Liesegang
50,595 PointsHi Joseph Beard-Maza !
Write a function called mathOperation that takes a math operation (as defined in the editor) as the first input
==> func mathOperation(mathOp: (Int, Int) -> Int
, two integers on which we carry out the math operation
==> , a: Int, b: Int)
, and a return type of Int
==> -> Int
The body of the function simply returns the result of the math operation you pass in
==> return mathOp(a, b)
func differenceBetweenNumbers(a: Int, b:Int) -> (Int) {
return a - b
}
// Enter your code below
func mathOperation(mathOp: (Int, Int) -> Int, a: Int, b: Int) -> Int {
return mathOp(a, b)
}
durul
62,690 Pointsthanks
Antonija Pek
5,819 Pointsfunc mathOperation(mathOp: (Int, Int) -> Int, a: Int, b: Int) -> Int
Can somebody explain this syntax to me. I don't understand it at all.
Karl Metum
3,447 PointsmathOp: (Int, Int) -> Int specifies that the first parameter passed to the function mathOperation must be a function that takes two Int parameters and returns an Int.
Joseph Maza
9,184 PointsJoseph Maza
9,184 PointsThank you this helps a lot!
Christopher Mayfield
19,928 PointsChristopher Mayfield
19,928 PointsHolger Liesegang how come you don't need need parentheses around our second return type, like in the differenceBetweenNumbers function above?