Swift convert Integer to Int

Question

Swift convert Integer to Int

I am programming generics and have something that matches Integer . Somehow I need to do this on a specific Int that I can use.

extension CountableRange
{
    // Extend each bound away from midpoint by `factor`, a portion of the distance from begin to end
    func extended(factor: CGFloat) -> CountableRange<Bound> {
        let theCount = Int(count) // or lowerBound.distance(to: upperBound)
        let amountToMove = Int(CGFloat(theCount) * factor)
        return lowerBound - amountToMove ..< upperBound + amountToMove
    }
}

The error is here on let theCount = Int(count)

. What states:

Cannot call initializer for type 'Int' using argument list of type '(Bound.Stride)'

The error may be more helpful at first as it CountableRange

identifies it Bound.Stride

as SignedInteger

( source ). So a mistake could tell me that.

So, I know what it is Integer

, but how can I use the value Integer

?

+3

swift

Full Decent 05 May '17 at 16:55

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3 answers

this should work for you since swift 3.0

let theCount:Int32 = Int32(count);

0

Harshal 05 May '17 at 17:15

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If you really need Int

to try this instead:

let theCount = Int(count.toIntMax())

The method toIntMax()

returns this integer using Swifts with a wide native integer type (i.e. Int64

on 64-bit platforms).

0

Paulo mattos 05 May '17 at 17:16

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Martin R · Accepted Answer · 2017-05-05T17:15:24+0000

You can use numericCast()

to convert between different integer types. As the documentation says:

Typically used to convert to any context sensitive integer type.

In your case:

extension CountableRange where Bound: Strideable {

    // Extend each bound away from midpoint by `factor`, a portion of the distance from begin to end
    func extended(factor: CGFloat) -> CountableRange<Bound> {
        let theCount: Int = numericCast(count)
        let amountToMove: Bound.Stride = numericCast(Int(CGFloat(theCount) * factor))
        return lowerBound - amountToMove ..< upperBound + amountToMove
    }
}

The restriction Bound: Strideable

must be made arithmetic lowerBound - amountToMove

and upperBound + amountToMove

.

Swift convert Integer to Int

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