Convert if ((loc = [player locateCardValue:8]) > - 1) to Swift 3

Question

How would you convert this Objective-C

if ((loc = [player locateCardValue:8]) > -1) {

to Swift 3?

[player locateCardValue] returns an integer of the location where the card '8' was found. Returning -1 means it didn't find the card '8'.

I could use ...

let loc = player.locateCard(withValue: 8)
if loc > -1 {

but I have multiple nesting of IF's and it would get really messy.

Both the Swift and the Objective-C version have an `if`… – Amin Negm-Awad Jan 18 '17 at 16:51 — Amin Negm-Awad, Jan 18 '17 at 16:51

score 5 · Answer 1 · edited Jan 18 '17 at 16:27

5

Maybe the best approach is not to convert it "as is", but to make it more Swift-like.

In this case I think I would change the locateCard to return an Optional<Int> and return nil when the card is not found.

func locateCard(withValue: Int) -> Card? {
    // return the position if found, nil otherwise
}

Then, you can just write

if let card = player.locateCard(withValue: 8) {

}

edited Jan 18 '17 at 16:27

Luca Davanzo

answered Jan 18 '17 at 16:26

Marcos Crispino

For the protocol: The Objective-C piece of code isn't Objective-C'ish. – Amin Negm-Awad Jan 18 '17 at 16:44
How does reduce the number of nested `if`? – Amin Negm-Awad Jan 18 '17 at 16:51

score 2 · Accepted Answer · answered Jan 18 '17 at 16:26

2

Your best option is to convert locateCardValue to return an Optional Int?. Then you could simply do

if let loc = player.locateCard(withValue: 8) {
    // ...
}

Or you could use a switch statement

switch player.locateCard(withValue: 8) {
case -1: print("No card.")
case 1: // ...
// etc.
}

answered Jan 18 '17 at 16:26

sdasdadas

Thanks. I guess I got hung up on keeping the -1 return value. Optional value works as well. – Johnne Jan 18 '17 at 16:51

2 Answers2