[swift-users] Bool to Int

[Adrian Zubarev]

In general this is a correct behaviour, because literals in Swift are untyped. Int does not have any initializer for a Bool so the compiler tries to find a type that might conforms to ExpressibleByBooleanLiteral for all possible initializer of Int (Int.init(_: TYPE)). This resolution decides to go with NSNumber in your case?!

The thing is, when you write Int(a > b), you’re passing a Bool and not a literal anymore. Here the compiler does not fallback to NSNumber anymore and reports you an error, because Int.init(_: Bool) does not exist.



-- 
Adrian Zubarev
Sent with Airmail

Am 21. November 2016 um 04:48:35, Rick Mann via swift-users (swift-users at swift.org) schrieb:

It seems I can't do this:

let r = Int(a > b)

but I can do it with a literal:

let r = Int(true)

I'd like to do this to implement signum without branching, but perhaps that's not possible.

--  
Rick Mann
rmann at latencyzero.com


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