[swift-evolution] Proposal: Deprecate optionals in string interpolation

Javier Soto javier.api at gmail.com
Thu May 19 12:09:42 CDT 2016


+1.

Instead of \(optional) having to do \(optional?. description ?? "") or
whatever fallback string you want is not that cumbersome and can prevent
Optional(Foo) sort of strings from appearing in user facing text, which I
have seen in several shipping app store apps already.
On Thu, May 19, 2016 at 9:07 AM Jeremy Pereira via swift-evolution <
swift-evolution at swift.org> wrote:

> -1
>
> This seems to me like crippling string interpolation just because
> sometimes we make mistakes. 99% of the time, if I interpolate an optional,
> it’s because I want it that way. I don’t want to have to put up with a
> warning or write the same boilerplate 99% of the time just to flag up the
> 1% more easily. Sorry.
>
> > On 18 May 2016, at 19:50, Krystof Vasa via swift-evolution <
> swift-evolution at swift.org> wrote:
> >
> > The string interpolation is one of the strong sides of Swift, but also
> one of its weaknesses.
> >
> > It has happened to me more than once that I've used the interpolation
> with an optional by mistake and the result is then far from the expected
> result.
> >
> > This happened mostly before Swift 2.0's guard expression, but has
> happened since as well.
> >
> > The user will seldomly want to really get the output
> "Optional(something)", but is almost always expecting just "something". I
> believe this should be addressed by a warning to force the user to check
> the expression to prevent unwanted results. If you indeed want the output
> of an optional, it's almost always better to use the ?? operator and supply
> a null value placeholder, e.g. "\(myOptional ?? "<<none>>")", or use
> myOptional.debugDescription - which is a valid expression that will always
> return a non-optional value to force the current behavior.
> >
> > Krystof
> >
> > _______________________________________________
> > swift-evolution mailing list
> > swift-evolution at swift.org
> > https://lists.swift.org/mailman/listinfo/swift-evolution
>
> _______________________________________________
> swift-evolution mailing list
> swift-evolution at swift.org
> https://lists.swift.org/mailman/listinfo/swift-evolution
>
-- 
Javier Soto
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://lists.swift.org/pipermail/swift-evolution/attachments/20160519/2b214450/attachment.html>


More information about the swift-evolution mailing list