> On 18 Jul 2016, at 21:32, Sean Heber via swift-evolution
> <[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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