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shane reichefeld
Courses Plus Student 2,232 PointsCan someone walk me through this problem step by step so i can better understand?
Help please
struct Book {
let title: String
let author: String
let price: String?
let pubDate: String?
}
1 Answer
Josh Reynolds
10,734 Pointshey shane reichefeld,
First off, we need to create a failable initialiser that accepts a dictionary as an input. Remember a failable initialiser is one that can return nil after initialisation, done so when values supplied fall outside a certain range etc or are missing. Then we will use a guard statement to check bad cases first. We will store our values in temporary constants to then apply to our struct properties.
struct Book {
let title: String
let author: String
let price: String?
let pubDate: String?
init?(dict: [String: String]) {
guard let title = dict["title"], author = dict["author"] else {
return nil
}
self.title = title
self.author = author
// here we don't need self as it is not ambiguous. We can assign the value directly to the property
price = dict["price"]
pubDate = dict["pubDate"] // same here
}