Great point; an infinite loop syntax would make a lot of sense. It seems good
for it to have its own syntax, considering you must have a `break` or `return`
to escape it. `while true { }` provides the same functionality, though it
seems a bit less direct in its purpose than `repeat { }` could.
> On Jul 18, 2016, at 4:16 PM, Haravikk <[email protected]> wrote:
>
>
>> On 18 Jul 2016, at 21:32, Sean Heber via swift-evolution
>> <[email protected] <mailto:[email protected]>> wrote:
>>
>> I’ve wanted this myself, too, so I’m generally +1, although I’ve also
>> wondered if maybe this syntax should be changed somehow. I’ve not put a lot
>> of thought into it, and this perhaps has come up before, but I sort of
>> wonder.. would it make more sense to get rid of the trailing “while”
>> entirely?
>>
>> Here’s what I’m thinking:
>>
>> This repeats forever - infinite loop:
>>
>> repeat {}
>>
>> And to get out of the infinite loop, you’d just use an if or guard the same
>> way you might in any other loop in some cases:
>>
>> repeat {
>> let success = doSomething()
>> guard success else { break }
>> }
>>
>> We could potentially even warn if you use a repeat {} without there being a
>> break inside the body somewhere.
>>
>> This way, we eliminate a special syntactical form (repeat/while has always
>> felt weird in every brace-based language I’ve used) and just piggyback on
>> the existing break/continue/guard/if mechanisms that are already there and
>> common. Then we also don’t need to have a special “weird” rule where the
>> scope of variables change magically for repeat/while.
>>
>> l8r
>> Sean
>
> That's a very interesting alternative, especially with a warning when there's
> no break (or return), and it would be clearer about the scope. Actually now I
> think about it, the repeat/while is a little odd in Swift since the while
> condition doesn't require parenthesis, which is great for a regular while or
> if condition because the braces give it structure, but that's not quite the
> case with the repeat/while.
>
> I'm fine either way, but this should be explored as well; guard in particular
> goes well this style of repeat syntax. More interestingly though is that this
> would actually allow us to write while loops as:
>
> repeat {
> guard someCondition() else { break }
> doSomething()
> }
>
> while would essentially just become a shorthand.
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