Optionals and Dictionary

optionals_basic.swift

let netWorthOfBillionaires = ["Bill Gates":78.5,"Carlos Slim Helu":71,"Warren Buffett":70.9]

let possibleNetWorth = netWorthOfBillionaires["Tim Cook"]

//Type of the possibleNetWorth is inferred to Double?

//Know what! Tim cook is not a billionair yet. His net worth is aroung $400 million
//Thats why he is not in our list. But who knows. He might becomes a billionair

if (possibleNetWorth != nil){
    
    let netWorth = possibleNetWorth!
    // ! Force the value out of optional
    println("Tim Cook's net worth in billions : \(netWorth)")
}

// But this is so common swift has more eligent way to do this

if let netWorth = possibleNetWorth {
    println("Tim Cook's net worth in billions : \(netWorth)")
}