Clean example of using Swift 1.2's improved optional binding via http://nshipster.com/swift-1.2/

optionals.swift

var users: [User] = []

// load and parse the JSON into an array
if let
    path     = NSBundle.mainBundle().pathForResource("users", ofType: "json"),
    url      = NSURL(fileURLWithPath: path),
    data     = NSData(contentsOfURL: url),
    userList = NSJSONSerialization.JSONObjectWithData(data, options: nil, error: nil) as? [[String: AnyObject]] 
{
    // extract individual users
    for userDict in userList {
        if let
            id      = userDict["id"] as? Int,
            name    = userDict["name"] as? String,
            email   = userDict["email"] as? String,
            address = userDict["address"] as? [String: AnyObject]
        {
            users.append(User(id: id, name: name, ...))
        }
    }
}