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

Chris Lattner clattner at apple.com
Fri Feb 12 11:23:18 CST 2016


> On Feb 12, 2016, at 9:15 AM, Amir Michail via swift-evolution <swift-evolution at swift.org> wrote:
> 
> 
>> On Feb 12, 2016, at 12:09 PM, Radosław Pietruszewski <radexpl at gmail.com> wrote:
>> 
>> I think what you mean is `fatalError()`.
>> 
>> You can’t do what you suggest, because you can’t prove that the expression passed to precondition will evaluate to false. (You theoretically could if the compiler checked for you passing `false`, but that makes no sense. Just go with `fatalError` or `preconditionFailure`.)
>> 
> 
> What’s wrong with having the compiler explicitly check for “false”?

Weird special cases make the compiler less predictable.

-Chris


More information about the swift-evolution mailing list