Storing Ranges in an Array in Swift

Question

I need to create an array whose objects are of type Range. But creating an array like below produces an error "Reference to generic type 'Range' requires arguments in <...>"

var ranges:Array<Range> = []

Basically, what I'm trying to accomplish is to create a list of ranges that will serve as a step function to generate a random type. I've done this without using array, but as I add more types I feel the need to just loop them over an array. My problem is that ranges somehow cannot be stored in an Array in Swift. Here's my old code that worked.

        let twisterUpperRange = UInt32(roundf(twisterRate * 1_000))
        let bombUpperRange = UInt32(roundf(bombRate * 1_000)) + twisterUpperRange
        let blindUpperRange = UInt32(roundf(blindRate * 1_000)) + bombUpperRange

        let randomNumber = arc4random_uniform(1_000) + 1

        var powerupType:PowerupType
        switch randomNumber {
        case 0...twisterUpperRange:
            powerupType = PowerupType.TwisterType
        case twisterUpperRange...bombUpperRange:
            powerupType = PowerupType.BombType
        case bombUpperRange...blindUpperRange:
            powerupType = PowerupType.BlindType
        default:
            powerupType = PowerupType.NormalType
        }

        return powerupType

Are your ranges all going to be the same type (i.e. UInt32)? If so, you can just do: var ranges: Array<Range<UInt32>>. — Mike S
– Mike S, Commented Sep 25, 2014 at 2:51

Sergey Kalinichenko · Accepted Answer · 2014-09-25 02:59:12Z

3

The error means that Swift Range is generic a generic type on the type of the interval ends:

var ranges : Array<Range<UInt32>> = []
let blindRate = 0.3
let twisterRate = 0.5
let bombRate = 0.2
let twisterUpperRange = UInt32(twisterRate * 1_000)
let bombUpperRange = UInt32(bombRate * 1_000) + twisterUpperRange
let blindUpperRange = UInt32(blindRate * 1_000) + bombUpperRange
ranges.append(0...twisterUpperRange)
ranges.append(twisterUpperRange...bombUpperRange)
ranges.append(bombUpperRange...blindUpperRange)
print(ranges)

Demo.

edited Sep 25, 2014 at 2:59

answered Sep 25, 2014 at 2:53

Sergey Kalinichenko

729k85 gold badges1.2k silver badges1.6k bronze badges

Sign up to request clarification or add additional context in comments.

Collectives™ on Stack Overflow

Storing Ranges in an Array in Swift

1 Answer 1

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

Comments

Your Answer

Sign up or log in

Post as a guest

Related