CODEWITHSUNDEEP
arraysswiftstringcharacter2d
Phontaine Judd
Phontaine Judd

Reputation: 438

Swift get array of strings from 2d array

Here is my code:

var parentList = [String]()

for user in MPUser.array {
    if user.childParent == "parent" {
        parentList.append(user.firstName)
    }
}

guard parentList.contains((selectedSecondJob?.assigned)!) else {
    print("payday has to be a parent, yo!")
    return
}

It works, but I know I can make it more "Swifty" by using a higher order function like flatMap.

Here's what I tried:

let parentListTEST = MPUser.array.flatMap({ $0.childParent })

But it returns an array of Characters, not Strings. Why? The MPUser array is an array of structs that clearly defines the "parent" parameter as a String, not Character.

How do I get a new array from my MPUser array that just has the names of the parents as Strings and not Characters?

Upvotes: 0

Views: 165

Answers (2)

Shehata Gamal
Shehata Gamal

Reputation: 100503

You can try either

let parentListTEST = MPUser.array.filter { $0.childParent == "childParent" }.map { $0.firstName }

Or

let parentListTEST = MPUser.array.compactMap { $0.childParent == "childParent" ?  $0.firstName : nil }

Upvotes: 1

Alexander
Alexander

Reputation: 63271

Use map.

flatMap flattens nested collections. You're mapping over a list of Users, getting an array of childParent Strings (which are themselves collections of Character), which flatMap is flattening out into a single array.

You just want the mapping without the flattening, so just use map.

Upvotes: 1

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