[swift-evolution] [swift-build-dev] SE-0151: Package Manager Swift Language Compatibility Version

[Martin Waitz]

Hello Rick,

thanks for the explanation!

Am 2017-02-08 17:55, schrieb Rick Ballard:
> I believe that the reason this was desired is because we expect that
> package authors may wish to conditionally adopt new Swift 4 language
> features without breaking their ability to build with Swift 3, using
> conditional compilation blocks, e.g.
> 
>  #if swift(>=4.0)
>  // Swift 4 code goes here
>  #endif
> 
> With this proposal, you can do this by specifying [3, 4], in which
> case the Swift 4 compiler will compile it as Swift 4 code, and use the
> code inside the conditional compilation block, while the Swift 3
> compiler will also be able to compile it (as Swift 3 code), skipping
> the conditional compilation block.

That makes sense.

+1 :-)

-- 
Martin