[swift-evolution] deinit and failable initializers

[Charles Srstka]

On Jan 26, 2016, at 11:15 AM, Chris Eidhof via swift-evolution <swift-evolution at swift.org> wrote:
> 
> class MyArray<T> {
>     var pointer: UnsafeMutablePointer<T>
>     var capacity: Int
>     
>     init?(capacity: Int) {
>         pointer = UnsafeMutablePointer.alloc(capacity)
>         if capacity > 100 {
>             // Here we should also free the memory. In other words, duplicate the code from deinit.
>             return nil
>         }
>         self.capacity = capacity
>         
>     }
>     
>     deinit {
>         pointer.destroy(capacity)
>     }
> }

In Swift, this sort of pattern is pretty rare. In the cases where you do need to manually allocate memory, you can always wrap the initializer in a “do” block, and release the memory in “catch”.

I don’t think this is a big issue.

Charles