[swift-evolution] [Draft] Tuple-Based Compound Optional Binding

[Xiaodi Wu]

This has been suggested before, I believe. The core team has weighed in
several times; it seemed like there was some disagreement amongst them
whether the current syntax is the wisest, but the concluding statement
seemed uncontroversial: "I don't think it's something we can change."

Source:
http://article.gmane.org/gmane.comp.lang.swift.evolution/15879/


On Mon, Jun 13, 2016 at 10:32 PM, Patrick Smith via swift-evolution <
swift-evolution at swift.org> wrote:

> If Pyry’s suggestion remained the preferred way of unwrapping a tuple,
> could it also become the only way for unwrapping a single item?
>
> guard case let a? = opt1 {
> ...
> }
>
> Or even shortened for matching optionals only:
>
> guard let a? = opt1 {
> ...
> }
>
> Or even as has often been requested, to keep the same name:
>
> guard let opt1? {
> ...
> }
>
> Multiples:
>
> guard let (opt1?, opt2?, opt3?) {
> ...
> }
>
> guard let (a?, b?, c?) = (opt1, opt2, opt3) {
> ...
> }
>
> Sorry, not trying to derail, but it always has seemed like something
> shorter and more self explanatory could be made for optionals. `?` in
> pattern matching is a special syntax anyway, so why not make this common
> use case easier?
>
> Patrick
>
> _____________________________
> From: Pyry Jahkola via swift-evolution <swift-evolution at swift.org>
> Sent: Sunday, June 12, 2016 10:04 PM
> Subject: Re: [swift-evolution] [Draft] Tuple-Based Compound Optional
> Binding
> To: Brent Royal-Gordon <brent at architechies.com>
> Cc: swift-evolution List <swift-evolution at swift.org>
>
>
>
>
> On 12 Jun 2016, at 14:46, Brent Royal-Gordon via swift-evolution <
> swift-evolution at swift.org> wrote:
>
> guard let (a, b, c) = (opt1, opt2, opt3) else { ... }
>
>
> You mention `guard case` in the motivation, but I think for the
> uninitiated reader it would be fair to point out that the following example
> already works equivalently, with only a few extra characters:
>
> guard case let (a?, b?, c?) = (opt1, opt2, opt3) else { ... }
>
>
> Aside of that, it's yet more magic to our `if let` syntax but I don't
> mind, it would be useful at times.
>
> — Pyry
>
>
>
>
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>
>
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