Bool to Int

Using Swift
14

Where is your problem here? It’s simple and easy ;)

extension Integer {
     
    init(_ boolean: Bool) {
         
        self = boolean ? 1 : 0
    }
}

Int(10 > 4)
UInt32(1 <= 2)

···

--
Adrian Zubarev
Sent with Airmail

Am 22. November 2016 um 00:54:47, Rick Mann via swift-users (swift-users@swift.org) schrieb:

On Nov 21, 2016, at 15:09 , Marco S Hyman <marc@snafu.org> wrote:

Except it does, because if I write

let a = 2

a is of type Int (at least, according to Xcode's code completion).

and if you write

let b = 2 + 0.5

2 is treated as a double. The type of the literal “2” varies with context. Do you also find that inconsistent and confusing?

Nope. I can see how the promotion works. Also, Xcode would tell me b is a Double.

But this gives inconsistent results:

let t = true

let a = Int(true)
let b = Int(t) // Error

I find this to be very inconsistent and confusing.

t is a Bool and there is no automatic conversion from Bool to Int.

true is not a Bool. It may be treated as a Bool depending upon context. In the line `let t = true` it is treated as a Bool. In `let a = Int(true)` it is treated as an NSNumber (assuming you import foundation).

That may be what's happening, but it's still confusing and unintuitive. That something is lost in the transitivity of going through a variable, aside from "literalness", is confusing.

And really, it would be nice if the language provided a fast way of getting an number "1" out of a Bool variable true (and 0 out of false). But that conversation is a bigger can of worms than I care to open right now.

--
Rick Mann
rmann@latencyzero.com

_______________________________________________
swift-users mailing list
swift-users@swift.org
https://lists.swift.org/mailman/listinfo/swift-users

1 Like