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

Jacob Bandes-Storch jtbandes at gmail.com
Wed May 18 17:48:47 CDT 2016

+1, personally I have taken to using `x+"str"+y` instead of
`"\(x)str\(y)"`, if x/y are strings, so I can get a compile-time error if I
do this accidentally.

But I do see the appeal of being able to print("the data: \(data)") for
simple use cases. Didn't someone earlier propose some modifiers/labels like
"\(describing: x)" ?

On Wed, May 18, 2016 at 11:50 AM, 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
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://lists.swift.org/pipermail/swift-evolution/attachments/20160518/4436f7fa/attachment.html>

More information about the swift-evolution mailing list