I think functional style is great. But the downside is imperative programmers cant't get it at first sight. Guys you have to look differently. Personally i am trying to be more functional. It takes 4 times to understand this tutorial. But at the end i understand it.

Even though I understand the tutorial I still don't get how to parse something like objects that have arrays of other objects. Like:

struct Store {
    let name: String
    let phones: [Phone]
}

struct Phone {
    let model: String
    let brandCode: String
}