[swift-evolution] Proposal: Initialization should not be required in precondition(false) case.

[Ross O'Brien]

It would be really helpful if you could describe the problem you're
experiencing so I don't have to guess what it is from your example code.

Am I guessing right if I say that you want a change to Swift such that a
switch initialisation can be 'force-unwrapped', such that if none of the
cases apply, the app crashes, in a more explicit fashion?

I've written code like this, but I've tended towards 'default:
fatalError()', which wouldn't be covered by your suggestion. 'precondition'
isn't at fault here.

Just as a digression, I've just learned that 'precondition(false)' doesn't
cause any immediately following code to receive the compiler warning 'will
never be executed' that code in a 'if false { ... }' does. So that would be
nice.

On Fri, Feb 12, 2016 at 3:59 PM, Amir Michail via swift-evolution <
swift-evolution at swift.org> wrote:

> For example:
>
> let x:Int
> if … { x = 1 }
> else if … { x = 2 }
> else { precondition(false) } // no initialization needed
>
> Similarly,
>
> let x:Int
> switch ... {
> case …: x = 1
> case …: x = 2
> default: precondition(false) // no initialization needed
> }
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