Swift Closures

gistfile1.rs

// old fashion way to pass a sorting function
func backwards(s1: String, s2: String) -> Bool {
    return s1 > s2
}
var reversed = sort(names, backwards)

// with closures, the {} denotes a function, everythig before 'in' keyword is function definition
reversed = sort(names, { (s1: String, s2: String) -> Bool in
    return s1 > s2
    })

// one lined
reversed = sort(names, { (s1: String, s2: String) -> Bool in return s1 > s2 } )

// infering types
reversed = sort(names, { s1, s2 in return s1 > s2 } )

// implicit returns
reversed = sort(names, { s1, s2 in s1 > s2 } )

// short hand arguments
reversed = sort(names, { $0 > $1 } )

// using the operator as a function
reversed = sort(names, >)