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iOS Closures in Swift 2 Closure Expressions Closure Expression Shorthand

Agustin Mendoza
Agustin Mendoza
5,247 Points
Posted by Agustin Mendoza
Agustin Mendoza
5,247 Points

Choosing the best shorthand syntax possible Could someone help me figured out why this shorthand syntax is not working?

I'm having some trouble on the code challenge at the end. In it you're asked to:

"...change the map function to use a closure expression rather than the doubleValue function. Use all the shorthand syntax possible to make it concise."

This is the code for the challenge:

func doubleValue(i: Int) -> Int { return i * 2 }

let doubler = doubleValue let doubledValues = [1,2,3,4].map(doubler)

This is what I came out with ( Xcode is not showing any errors )

func doubleValue(i: Int) -> Int { return i * 2 }

let doubler = doubleValue let doubledValues = [1,2,3,4].map(){ $0 * 2 }

Thank you in advance

1 Answer

Brandon Mahoney
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Brandon Mahoney
iOS Development with Swift Techdegree Graduate 30,149 Points
Brandon Mahoney
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Brandon Mahoney
iOS Development with Swift Techdegree Graduate 30,149 Points

Well it appears you have to do the closure exactly as below for this one. This is the most concise way.

[1,2,3,4].map { $0 * 2 }