> On 29 Oct 2017, at 3:01 pm, Mike Kluev <mike.kl...@gmail.com> wrote:
>
>> On 29 October 2017 at 14:02, Johannes Weiß <johanneswe...@apple.com> wrote:
>>
>> Definitely not arguing with that. But there are (valid?) cases when you want
>> a recursive closure which doesn’t have a native recursion mechanism and then
>> `fix` can be useful I’d argue. I think more straightforward than
>>
>>>>>> recursive.c = { x in
>>>>>> (x == 0) ? 1 : x * recursive.c(x - 1)
>>>>>> }
>>
>
> you can do without "recursive.c":
>
> var factorial: ((Int) -> Int)!
>
> factorial = { n in
> n == 0 ? 1 : n * factorial(n - 1)
> }
That’s nicer, thanks!
>
> factorial(5) // 120
>
>
>> . But fortunately have local functions, I can only recall wanting a
>> recursive closure once.
>>
>
> in down to earth practical programming even if i didn't have local functions
> i probably wouldn't bother abusing closures to implement recursion, would
> just used what's available: methods. and if there is some extra state to pass
> from the outer scopes, well, so be it, either via parameters of via some
> instance variables, etc. wasn't too much of a problem in good old C/C++. in a
> way, knowing exact state you want to pass and passing it explicitly organises
> the code and the reasoning about it.
>
> Mike
>
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