[webkit-dev] Initializing member variables

[Gerald Squelart]

+1 for { } as well, for all the mentioned good reasons.

But just to be complete, there's one exception that should probably be noted if/when we document this:
For classes that have a constructor taking `std::initializer_list<T>` and other constructors that take `T` (+ conversions), using braced-initialization will *always* call the initializer_list one! In this case, we'd need to use parentheses if another constructor was wanted. E.g.: `std::vector<int> vb { 3, 2 }` -> [ 3 2 ], vs `std::vector<int> vp(3, 2);` -> [ 2 2 2 ] (3 copies of value 2)!
At a glance, I haven't found WK classes that have both types of competing constructors together, so hopefully this should be a rare issue. May be worth another guideline, like "If you define a constructor taking std::initializer_list<type>, avoid defining other constructors for similar types"?

Cheers,
Gerald

> On 24 Sep 2024, at 02:35, Geoff Garen via webkit-dev <webkit-dev at lists.webkit.org> wrote:
> 
> +1 for { } because I like catching bugs.
> 
> But also: If Chris is right that { } is the only way to handle types without constructors, and the goal is to pick one syntax, then { } is the only possible solution, because standardizing on = would require exceptions for types without constructors.
> 
> Thanks,
> Geoff
> 
>> On Sep 20, 2024, at 2:29 PM, Yusuke Suzuki via webkit-dev <webkit-dev at lists.webkit.org> wrote:
>> 
>> I prefer { } style.
>> It can catch implicit narrowing bugs, which does not work with = style.
>> 
>> Best regards,
>> - Yusuke
>> 
>>> On Sep 19, 2024, at 4:13 PM, Jean-Yves Avenard via webkit-dev <webkit-dev at lists.webkit.org> wrote:
>>> 
>>> 
>>> 
>>>> On 20 Sep 2024, at 7:55 AM, Ryosuke Niwa via webkit-dev <webkit-dev at lists.webkit.org> wrote:
>>>> 
>>>> 
>>>> Should we do:
>>>> 
>>>> struct Foo {
>>>>     int bar = 0;
>>>> }
>>>> 
>>>> Or
>>>> 
>>>> struct Foo {
>>>>     int bar { 0 };
>>>> }
>>>> 
>>>> We do both at the moment.
>>>> 
>>>> - R. Niwa
>>> 
>>> I think `int bar = 0` reads better.
>>> 
>>> I only ever see (and use) { } and I thought that was the proper coding style.
>>> 
>>> I’m surprised it’s not in our guidelines. 
>>> 
>>> Jean-Yves
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