How to mutate Values inside a Array - arrays

Question

I need to mutate the following array:
struct Person {
var name: String
var age = 0
}
func showPersonArray() -> [Person] {
var dataArray = [Person]()
dataArray.append(Person(name: "Sarah_Yayvo", age: 29))
dataArray.append(Person(name: "Shanda_Lear", age: 45))
dataArray.append(Person(name: "Heidi_Clare", age: 45))
return dataArray
}
How could I split the "name"-key into two keys: "givenName" and "familyName".
Some nice person gave me this code before:
let arraySeparated1 = dataArray.map { $0.substring(to: $0.range(of: "_")!.lowerBound) }
let arraySeparated2 = dataArray.map { $0.substring(from: $0.range(of: "_")!.upperBound) }
Is it possible to make the mutation inside the struct?
The function showPersonArray() is only for demo and test.
Maybe there is a way to work with a target struct, like this:
struct Persontarget {
var familyname: String
var givenName: String
var age = 0
}
struct Person: Array -> [Persontarget] {
var name: String
var age = 0
// Here the split/mutating code
return [PersonWithTwoNames]
}
Or with an String extension. Possibly my question sounds pretty newby-like, but i´m trying the whole day...
Thanks everyone!

Answer 1

I would write an initializer on the new Person type, which initializes it from the old person type (which I called LegacyPerson):
import Foundation
struct LegacyPerson {
let name: String
let age: Int
}
func getPersonArray() -> [LegacyPerson] {
return [
LegacyPerson(name: "Sarah_Yayvo", age: 29),
LegacyPerson(name: "Shanda_Lear", age: 45),
LegacyPerson(name: "Heidi_Clare", age: 45)
]
}
struct Person {
let familyName: String
let givenName: String
let age: Int
}
extension Person {
init(fromLegacyPerson person: LegacyPerson) {
let index = person.name.range(of: "_")!
self.init(
familyName: person.name.substring(from: index.upperBound),
givenName: person.name.substring(to: index.lowerBound),
age: person.age
)
}
}
let people: [Person] = getPersonArray().map(Person.init)
people.forEach{ print($0) }

Answer 2

Create a method or computer variable for your Person class that returns what you want.
func firstName() -> String {
return self.substring(to: $0.range(of: "_")!.lowerBound)
}
You should not force cast though

Answer 3

with help of computed property defined in an extension
struct Person {
let name: String
let age: Int
}
let person = Person(name: "Maria_Terezia", age: 300)
extension Person {
var names:[String] {
get {
return name.characters.split(separator: "_").map(String.init)
}
}
}
for name in person.names {
print(name)
}
prints
Maria
Terezia