[swift-evolution] ternary operator ?: suggestion

[David Hart]

Best proposition since, but still more verbose than the ternary operator.

> On 04 Dec 2015, at 18:27, David Owens II <david at owensd.io> wrote:
> 
> There’s no need for the “then" keyword if you just allow if-expressions as well.
> 
> ```
> let result = if condition { 1 } else { 2 }
> ```
> 
> Or more verbosely:
> 
> ```
> let result =
>     if condition {
>         return 1
>     }
>     else {
>         return 2
>     }
> ```
> 
> The same could be for switch statements as well.
> 
> ```
> let result = switch item {
>     case foo: 1
>     case bar: 2
> }
> ```
> 
> The above assume implicit returns on single-line statements on the condition/case branches.
> 
> -David
> 
>> On Dec 3, 2015, at 11:26 PM, David Hart <david at hartbit.com> wrote:
>> 
>> I also tend to agree but I don't like the ordering in the Python version and would rather see the introduction of the then keyword
>> 
>>> On 04 Dec 2015, at 06:08, Sean Heber <sean at fifthace.com> wrote:
>>> 
>>> I agree that using ? for ternary feels.. uncomfortable in Swift. I wouldn't mind seeing Python-style or just eliminating it entirely in favor of simplicity.
>>> 
>>> l8r
>>> Sean
>>> 
>>>> On Dec 3, 2015, at 10:48 PM, Dan Appel <dan.appel00 at gmail.com> wrote:
>>>> 
>>>> I agree that ternary can make code unreadable, especially so with the ‘?’. I personally like the Haskel option the most, but it introduces a new keyword ‘then’, which isn’t great either. Python’s "y if x else z" is therefore, in my opinion, the best alternative.
>>>> 
>>>> Also, I found it interesting how split the Rust community was about removing the ternary operator.
>>>> 
>>>> — 
>>>> Dan Appel
>>>> 
>>>>> On Thu, Dec 3, 2015 at 7:58 PM J. Cheyo Jimenez <cheyo at masters3d.com> wrote:
>>>>> Would you consider replacing the C style ?: ternary operator to something that does not use the question mark and colon ? 
>>>>> 
>>>>> The use of "?" can be confusing when speed reading code with optionals. 
>>>>> 
>>>>> Consider this code as somebody learning swift as their first language.
>>>>> let result = !condition ? 1 : 2
>>>>> 
>>>>> 
>>>>> Some alternatives:
>>>>> 
>>>>> Haskel 
>>>>> if predicate then expr1 else expr2
>>>>> Python
>>>>> result = x if a > b else y
>>>>> The advantage of not using the question mark is that the language will be more consistency on the use of "?" to mean only optionals. 
>>>>> 
>>>>> 
>>>>> References:
>>>>> https://devforums.apple.com/message/1020139#1020139
>>>>> https://github.com/rust-lang/rust/issues/1698#issuecomment-3705066
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>>>>> swift-evolution at swift.org
>>>>> https://lists.swift.org/mailman/listinfo/swift-evolution
>>>> 
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