Select() from LINQ in swift 3.0? [duplicate]

Answer 1

map(_:)

let ranks = cards.map{ $0.Rank }

which is syntactic sugar for:

let ranks = cards.map({ (card: Card) -> Rank in
    return card.rank
})

The applied syntactic sugar includes:

1. Trailing closure syntax

   let ranks = cards.map { (card: Card) -> Rank in
       return card.rank
   }
   

2. Argument type inference

   let ranks = cards.map { card -> Rank in
       return card.rank
   }
   

3. Return type inference

   let ranks = cards.map { card in
       return card.rank
   }
   

4. Implicit return value

   let ranks = cards.map { card in
      card.rank
   }
   

5. Anonymous closure arguments

   let ranks = cards.map { $0.rank }
   

Check out the language guide section on closures (the Swift name for what C# calls lambdas) for more information,