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

[Xiaodi Wu]

Also, see:
https://github.com/apple/swift-evolution/blob/master/commonly_proposed.md


On Mon, Jun 13, 2016 at 11:06 PM, Xiaodi Wu <xiaodi.wu at gmail.com> wrote:

> 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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