I'll try profiling it (or looking at the generated assembly).
Thanks!
> On Nov 20, 2016, at 21:15 , Marco S Hyman <m...@snafu.org> wrote:
>
>> Is there a way that avoids branching?
>
> Don’t know. Have you profiled
>
> let r = a > b ? 1 : 0
>
> to know it is an issue?
>>
>> So, according to Xcode, "true" and "a > b" both have type "Bool". I don't
>> know why the compiler allows one and not the other, except that it's
>> literal, and I guess there's a "BoolLiteralConvertible" (or equivalent) for
>> the types.
>
> You are including foundation which gets you the bridging code.
>
> let r = Int(true)
>
> is an error without foundation. With foundation you get this:
>
> extension NSNumber : ExpressibleByFloatLiteral, ExpressibleByIntegerLiteral,
> ExpressibleByBooleanLiteral {
>
> // [snip]
>
> /// Create an instance initialized to `value`.
> required public convenience init(booleanLiteral value: Bool)
> }
>
> and this
>
> extension Int {
>
> public init(_ number: NSNumber)
> }
>
>
> which when combined make `let r = Int(true)` work. I haven’t profiled the
> code but would suspect that `let r = a > b ? 1 : 0` might be more efficient.
>
>
--
Rick Mann
rm...@latencyzero.com
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