[OT] Some neat ideas from the Kotlin language

[Daniel N via Digitalmars-d]

On Friday, 19 February 2016 at 21:30:37 UTC, Yuxuan Shui wrote:
>> I think the same applies to Swift. But I think you're supposed 
>> to use it like this:
>>
>> if let a = var {
>>   // a is no unwrapped
>> }
>
> But you would need to give the unwrapped value a new name.
>

Swift also has guard, which solves this issue.

func ex(a: Int?) {
     // unwrap (possible to add additional check if desired)
     guard let a = a where a > 0 else {
         return // fail
     }

     a.ok // a is now a plain validated Int
}